If you still have the trade under pending trades and if you don’t have any other trades open you can delete the PendingTrades db file in the db folder inside the data directory. At Account/Backup you can open the data directory. Make a backup first and shut down Bisq when deleting the file.
@Homard @alexej996 If there are similar cases you can give that advice as well. Just make sure the user don’t have any other trades open and he should do a backup!