Pending transactions on Linea work similarly to Ethereum, and sometimes they can get 'stuck'.
When you submit a transaction on Linea, it enters a memory pool (the mempool) where it is temporarily held before being added to a block. The Linea sequencer then adds the transaction to a block when it can. Sometimes, however, the transaction is never added to a block, and sits in the mempool indefinitely — stuck.
What can I do about it?
If you're not sure what actions you can take, we recommend using MetaMask Activity's Pending Transaction Troubleshooting tool. You can read more about how to use it here.
If you determine you want to cancel your transaction:
There are two methods you can use to cancel a pending transaction, and both of them are explained in MetaMask's article here.
If you are using the custom nonce method:
We need to deviate from the instructions at one point. In step 3 (or step 4, for Mobile) the article says: "Set your gas limit comparable to or slightly higher than your original transaction."
What we need to do is set a gas limit considerably lower than the astronomical value of the original transaction.
Since any unused gas units are returned to you, there is no harm in setting something higher than you need — although, obviously, to address the original problem, we need to set it low enough that it can be picked up and included in a block.
For this reason, we recommend you set your gas limit to 500,000, as a starting point.
If your transaction is still not picked up and confirmed, you could then start increasing the gas limit from 500,000.
If you run into any issues, or the method is unsuccessful, head to our Discord for help from other users or our Community team.