James Comey, the fired FBI director, allegedly has a memo that detailed a phone conversation with President Donald Trump. In that conversation, Comey claimed that the president asked him to let the investigation of Michael Flynn (a former Trump advisor) die. Comey revealed the memo through an associate to his, which memo was read on the phone to a New York Times reporter.
However, Comey never revealed the memo  to top officials at the Department of Justice.
Congress is seeking Comey’s testimony and access to the memo.