Generally, the more ways you provide them to ease the repayment, the easier it gets to receive the payment. As a result, it allows you to recover the amount faster and more easily. Also, do mention where they are supposed to send the reply. You might be unable to find another solution and decide to start court proceedings. In that case, you must have complied with the protocol properly. They might not take into account minor non-compliances. However, there shouldn’t be a major one. Otherwise, they will take action against you.