Server-to-Server OAuth not working with meeting report

I am trying to fetch meeting report of sub accounts using reportMeetingParticipants API by using Server to Server OAuth but its giving me this error:

{“code”:124,“message”:“Invalid access token.”}

I am generating new token upon every request. I have also tried to fetch meeting report of Master account but it gives same error. My master account and sub accounts are on Pro. I have also added scopes; meeting:read:admin, report:master and report:read:admin.