Ask for the decision in writing
If the refusal came over the phone, ask for a written final response. It should explain why the bank declined and how you can escalate. You usually need this letter, or proof that the bank ran out of time to reply, before an ombudsman will look at your case.
Check the reasons against the rules
- Which reimbursement rules did the bank apply, and to which payments?
- Did the bank say you were grossly negligent? What is that based on?
- Did any of your payments look unusual for your account, and did the bank warn you or intervene?
- Did the bank try to recover the money from the receiving bank?
Escalate to the ombudsman
Most countries have a free, independent financial ombudsman or dispute service. In the UK, you normally have six months from the date of the bank's final response to refer your complaint to the Financial Ombudsman Service.
Send your evidence, the bank's final response and a short explanation of why you disagree. The ombudsman looks at what is fair and reasonable, not only at the bank's own policy.
Getting help
You can do all of this yourself for free. Some people prefer help when there are many payments, several banks involved, or when dealing with it is simply too much. Either way, keep copies of everything.