<prompt> Human: If I understand correctly, once a debt is incurred, the creditor must accept payment in legal tender - like cash. That would be the entire idea behind legal tender.My friend had a problem with making a payment for a course already completed. She was given an invalid account number to make the payment to, and the office was absolutely obstinate about her requesting to fix the issue or let her pay by any other means in particular, in cash. As we were discussing it, someone suggested she just walks in there, slams the amount in cash on the desk and walks out. Obviously not the smartest move, but could one do something roughly along these lines to solve such a problem? How should that look?AFAIK they are not legally allowed to refuse cash. But what can be done if they do?  <response>: Cash can be legally refused if the contract used to incur the debt says it will not be accepted. 