How to create a Statement when some Transaction Codes are not mapped?

We are on EBS 12.2.5. We create bank statements in Cash management from BAI files that we receive from the Bank. Sometimes we run into a situation where the bank file has a transaction code that we have not seen before, and therefore not mapped. In such cases, the Bank Statement creation fails and no statement is created.

Is this expected behavior that even if 1 transaction in the file has an un-mapped transaction code, the entire file will fail to create a bank statement?

How do other companies handle this? I'm sure there are always situations where a new transaction code is encountered? What is the best practice to handle these exceptions so statements are still created and these exceptions end up as unreconciled items or something similar? basically, we do not want all the other transactions to not reconcile because of one un-mapped transaction.