did you have a vpn on because I had a vpn on and was trying to play at school (my school Wi-Fi has a firewall) and I tried to log onto my mine hut server and it said I had been black listed, I did some research and found out that the server thinks you are botting because you have a vpn on. I have submitted any appeal but I don't think its going to do anything.
not sure if this did help but good luck