Hi @Vonsoul,
This situation may happen when a lower fee (Gas price) was set.
You have the option to cancel the pending transaction in MetaMask. Information on how to do it can be found in this video: How to speed up or cancel ETH transaction with Trezor - YouTube
After you cancel the pending transaction, the ETH will be returned to your ETH address. You can then create another trade, make sure to set the Gas price high enough so the transaction can be confirmed in time.
You can use for example the following tool which tells you the estimated time for confirmation for a specific Gas price: https://etherscan.io/gastracker