<prompt> Translate the following text to SwahiliIn such instances, the Services request must be supported by testimony of a Postal Service witness that explains the rationale for the proposed multi-year test period.  <response>: Katika kesi kama hizo, ombi la Huduma lazima liunge mkono na ushuhuda wa shahidi wa Huduma ya Posta ambaye anaelezea sababu ya kipindi cha majaribio cha miaka mingi kilichopendekezwa. 