I heard a story about Rav Moshe (I could have the details slightly wrong) and Rav Shlomo Zalman
He make a Psak and wanted to know what Rav Shlomo Zalman’s opinion was on the matter. He sent a letter to Rav Shlomo Zalman for an answer. he did not receive one. Some time later he met up with Rav Shlomo Zalman and asked him why he did no reply to his letter and Rav Shlomo Zalman said he didnt remember receiving it. After some investigations Rav Shlomo Zalman found out that an askan had intercepted the letter and did not give it to Rav Shlomo Zalman