31 CFR §321.5

1. (a)By the Treasury. The Secretary of the Treasury, or a designee, may authorize a TRS Site to terminate the qualification of any paying agent at any time, following prior written notice of such action to the agent.
2. (b)At request of paying agent. A TRS Site will terminate the qualification of a paying agent upon its written request, provided the agent renders a final accounting for all redeemed securities and is found to have fully complied with the terms of its agreement and the applicable regulations and instructions.
3. (c)Reservation. Termination of the qualification as paying agent of any institution shall not prejudice the right of the Treasury to recover the amounts of any erroneous payment(s) made by the institution.