What can I do about a check that was encoded incorrectly?

Encoding errors are generally handled by adjustments sent between banks. You should notify your bank so they can investigate the error. Generally, banks require you to notify them of any error(s) within 30 days after the statement date. However, the time period for this prompt notification may vary by bank and State.

Your Deposit Account Agreement specifies your bank's specific time requirement. Take a look at that agreement and contact the bank directly regarding any alleged error.