If this concerns deposit account closings, I'm not aware of any regulatory considerations. If we know the customer wants the account closed,and they come to our new accounts staff, we generally use a close-out slip so we have a signature that they wanted the account closed and got their money.
However, if they just withdraw the money, the account will close out automatically after a certain number of days with a zero balance and there are no 'closing instructions' anyway.
However, if you have it in your policy that you need such instructions, and that's what he/she is criticizing, that's another matter.
Ho
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I hear and I forget. I see and I remember. I do and I understand.--Confucius