💡Troubleshooting Errors

Common error messages. Use the sidebar ➡️to jump to the error you're seeing.

Sometimes you may find yourself facing a problem that doesn't have a clear solution. These troubleshooting tips may help you solve problems you run into.

Issues on the Exchange

INSUFFICIENT_OUTPUT_AMOUNT

The transaction cannot succeed due to error: SupswapRouter: INSUFFICIENT_OUTPUT_AMOUNT. This is probably an issue with one of the tokens you are swapping.

the transaction cannot succeed due to error: execution reverted: supswaprouter: insufficient_output_amount.

You're trying to swap tokens, but your slippage tolerance is too low or liquidity is too low.

Solution

1. Refresh your page and try again later.

2. Try trading a smaller amount at one time.

3. Increase your slippage tolerance:

   1. Tap the settings icon on the liquidity page.

   2. Increase your slippage tolerance a little and try again.

4. Lastly, try inputting an amount with fewer decimal places.

Reason

This usually happens when trading tokens with low liquidity.

That means there isn't enough of one of the tokens you're trying to swap in the Liquidity Pool: it's probably a small-cap token that few people are trading.

However, there's also the chance that you're trying to trade a scam token which cannot be sold. In this case, SupSwap isn't able to block a token or return funds.

INSUFFICIENT_A_AMOUNT or INSUFFICIENT_B_AMOUNT

Fail with error 'SupswapRouter: INSUFFICIENT_A_AMOUNT' or Fail with error 'SupswapRouter: INSUFFICIENT_B_AMOUNT'

You're trying to add/remove liquidity from a liquidity pool (LP), but there isn't enough of one of the two tokens in the pair.

Solution

Refresh your page and try again, or try again later.

Still doesn't work?

1. Tap the settings icon on the liquidity page.

2. Increase your slippage tolerance a little and try again.

Reason

The error is caused by trying to add or remove liquidity for a liquidity pool (LP) with an insufficient amount of token A or token B (one of the tokens in the pair).

It might be the case that prices are updating too fast when and your slippage tolerance is too low.

Solution for nerds

OK, so you're really determined to fix this. We really don't recommend doing this unless you know what you're doing.

There currently isn't a simple way to solve this issue from the SupSwap website: you'll need to interact with the contract directly. You can add liquidity directly via the Router contract, while setting amountAMin to a small amount, then withdrawing all liquidity.

Approve the LP contract

Head to the contract of the LP token you're trying to approve. For example, here's the ETH/USDC pair: https://explorer.mode.network/address/0x58f3e81a600ce71c75e03da1927bfb2a50ccd3a2

1. Select Write Contract, then Connect to Web3 and connect your wallet.

2. In section "1. approve", approve the LP token for the router by entering

   1. spender (address): enter the contract address of the LP token you're trying to interact with

   2. value (uint256): -1

Add or Remove Liquidity

Head to the router contract: https://explorer.mode.network/address/0x082C1E810B6518a65ae61d9C07dc25d9ffe61Ae6?tab=write_contract

1. Select Write Contract and Connect to Web3 as above.

2. Find addLiquidity or removeLiquidity (whichever one you're trying to do)

3. Enter the token addresses of both of the tokens in the LP.

4. In liquidity (uint256), enter the uint256 number which you got from "balanceOf" above.

5. Set a low amountAMin or amountBMin: try 1 for both.

6. Add your wallet address in to (address).

7. Deadline must be an epoch time greater than the time the tx is executed.

This can cause very high slippage, and can cause the user to lose some funds if frontrun

SupswapRouter: EXPIRED

The transaction cannot succeed due to error: SupswapRouter: EXPIRED. This is probably an issue with one of the tokens you are swapping.

Try again, but confirm (sign and broadcast) the transaction as soon as you generate it.

This happened because you started making a transaction, but you didn't sign and broadcast it until it was past the deadline. That means you didn't hit "Confirm" quickly enough.

Supswap: TRANSFER_FAILED

The transaction cannot succeed due to error: execution reverted: Supswap: TRANSFER_FAILED.

Make sure you have 30% more tokens in your wallet than you intend to trade, or try to trade a lower amount. If you want to sell the maximum possible, try 70% or 69% instead of 100%. Caused by the design of Restorative Rebase tokens like tDoge or tBTC.\

Another possible cause of this issue is the malicious token issuer just suspended the trading for their token. Or they made selling action only possible for selected wallet addresses. Please always do your own research to avoid any potential fraud. If the token you are trying to swap but failed with this error code is coming from an airdrop, that is most likely a scam. Please do not perform any token approval or follow any links, your fund may be at risk if you try to do so.

Transaction cannot succeed

Try trading a smaller amount, or increase slippage tolerance via the settings icon and try again. This is caused by low liquidity.

Price Impact too High

Try trading a smaller amount, or increase slippage tolerance via the settings icon and try again. This is caused by low liquidity.

estimateGas failed

This transaction would fail. Please contact support

If you got this error while removing liquidity from a ETH pair:

Please select "Receive WETH" and retry.

If you got this error while trying to swap:

Please contact the project team of the token you're trying to swap. **** This issue must be resolved by the project team.

Cannot read property 'toHexString' of undefined

"Unknown error: "Cannot read property 'toHexString' of undefined"

When trying to swap tokens, the transaction fails and this error message is displayed. This error has been reported on mobile devices using Trust Wallet.

1. Attempt the transaction again with increased slippage allowance.

2. If 1. does not resolve your problem, consider using another wallet such as SafePal for your transaction.

Execution reverted: TransferHelper: TRANSFER_FROM_FAILED.

The transaction cannot succeed due to error: execution reverted: TransferHelper: TRANSFER_FROM_FAILED.

When trying to swap tokens, the transaction fails and this error message is displayed. This error has been reported across platforms.

Solution

1. Check to make sure you have sufficient funds available.

2. Ensure you have given the contract allowance to spend the amount of funds you're attempting to trade with.

Reason

This error happens when trading tokens with insufficient allowance, or when a wallet has insufficient funds.\

Out of Gas error

Warning! Error encountered during contract execution [out of gas]

You have set a low gas limit when trying to make a transaction.

Solution

Try manually increasing the gas limit (not gas price!) in your wallet before signing the transaction.

A limit of 200000 is usually enough.

The above example is from Metamask; check your wallet's documentation if you aren't sure how to adjust the gas limit.

Reason

Basically, your wallet (Metamask, Trust Wallet, etc.) can't finish what it's trying to do.

Your wallet estimates that the gas limit is too low, so the function call runs out of gas before the function call is finished.

ERC20: transfer amount exceeds allowance

Fail with error 'ERC20: transfer amount exceeds allowance'

Solution

1. Use Unrekt.net to revoke approval for the smart contract you're trying to interact with

2. Approve the contract again, without setting a limit on spend allowance

3. Try interacting with the contract again.

Reason

This happens when you set a limit on your spend allowance when you first approved the contract, then try to swap more than the limit.

ERC20: transfer amount exceeds balance

Fail with error 'ERC20: transfer amount exceeds balance'

You may be trying to send tokens that you don't have in your wallet (for example, trying to send a token that is already assigned to a pending transaction). In this case, just make sure you have the tokens you're trying to use.

Other issues

Provider Error

Provider Error No provider was found

This happens when you try to connect via a browser extension like MetaMask, but you haven’t installed the extension.

Solution

Install the official browser extension to connect, or read our guide on how to connect a wallet to SupSwap.

Unsupported Chain ID

Switch your chain to Mode Network. Check your wallet's documentation for a guide if you need help.

Already processing eth_requestAccounts. Please wait.

Make sure you are signed in to your wallet app and it's connected to Mode Network.

Internal JSON-RPC errors

"MetaMask - RPC Error: Internal JSON-RPC error. estimateGas failed removeLiquidityETHWithPermitSupportingFeeOnTransferTokens estimateGas failed removeLiquidityETHWithPermit "

Happens when trying to remove liquidity on some tokens via Metamask. Root cause is still unknown. Try using an alternative wallet.

Internal JSON-RPC error. { "code": -32000, "message": "insufficient funds for transfer" } - Please try again.

You don't have enough ETH to pay for the transaction fees. You need more BEP-20 network ETH in your wallet.

Error: [ethjs-query]

Error: [ethjs-query] while formatting outputs from RPC '{"value":{"code":-32603,"data":{"code":-32000,"message":"transaction underpriced"}}}"

Increase the gas limit for the transaction in your wallet. Check your wallet's documentation to learn how to increase gas limit.

Swap failed: Error: [ethjs-query] while formatting outputs from RPC '{"value":{"code":-32603,"data":{"code":-32603,"message":"handle request error"}}}'

Cause unclear. Try these steps before trying again:

1. Increase gas limit

2. Increase slippage

3. Clear cache