39 CFR § 3023.10
Rate or service inquiry contents
November 6, 2020
(a) A rate or service inquiry shall be in writing and should contain:
(1) The name, address, and telephone number of the inquiring party;
(2) Details regarding the Postal Service's action or inaction;
(3) A statement of facts supporting the inquiring party's allegations; and
(4) The specific relief being sought, if any.
(b) The Commission may waive any of the requirements listed in paragraph (a) of this section to serve the interests of justice.