Former national security adviser Michael Flynn has again declined a request to appear before the Senate Intelligence Committee, CNN reported early Wednesday, citing an unnamed source in Congress.

Investigators are reportedly interested in Flynn’s contacts with Russian officials during the transition and his failure to disclose payments he received from Russian firms.

The former Trump official previously refused a Senate Intelligence Committee request to appear in May, citing Fifth Amendment rights. At the time, Flynn’s lawyers argued that an “escalating public frenzy against him” created a a legally dangerous environment for Flynn, preventing him from testifying.

The Senate committee also issued subpoenas for documents from Flynn in May, and the former national security adviser reportedly agreed to turn over documents to the committee.