Please login here to find out the reason for your ban: https://pokemonrevolution.net/dashboard. If it doesn't say your account is banned, this can be caused by a few things, your account isn't banned but something on your connection is.
Are you using Proxy?
Try to not using it, and then test again
Are you trying to play at home/work/school?
Your school/work or any public connection, they could have had their IP blocked already or be blocking the game on their network, you would need to ask them to find if that's the case
It could also be your provider blocking the game, which case you could try contacting your internet provider to try and get it unblocked as seen in this post
You could also use a VPN although you should check you're allowed first
If you are indeed banned, please post an appeal here: https://pokemonrevolution.net/forum/viewforum.php?f=32