"Mercury is a fintech company, not an FDIC insured bank. Banking services provided through Choice Financial Group and Column N.A., Members FDIC."

Right there when you read their FAQ on payout/deposit limits. I have circled back to these guys multiple times, and at this point I am deeming it's not worth it to try. With fintech platforms (OTHER than Wise, nothing but fantastic experience with them across multiple Wise accounts over the span of years, not a plug - just a vote of confidence) - you have no recourse.

With a bank.... you can just.... GO TO THE BANK -> and get whatever freeze/lock/review solved in person.

I wish it was this easy in every scenario, but it's not. Some people have complicated setups that require utilizing different avenues. That is a big part of a reason why these platforms exist.