[tor-relays] DirAuths are blocking my node on Amazon EC2. Why?

Dear all, I have a Tor relay running on Amazon EC2 (IP range: 52.0.0.0/11) and for sometime I am receiving the messages: http status 400 ("Authdir is rejecting routers in this range.") response from dirserver 'X.X.X.X:80'. Please correct. The router disappeared from the Tor Directory and the consensus. Its a non-exit node and there seems to be some traffic going on. Was there a particular reason for the block or was this specific to my router only? Should I consider moving to a different provider or was I specifically targeted by the block and should not attempt moving somewhere else. My details: Nickname: Yankee2 IP: 52.25.145.191 Hash: CA631DB7F8E3E00A148D2D1D0BBD1B5710888D8E Best, Yousif