Not receiving emails from website anymore

Hello, 

I am trying to recover my AJ account and have not been receiving emails. I was told that it was because I have placed their email onto the suppression list in the past (I don't really remember doing that) and I would need to reach out to my provider to handle this. Do any of you guys know what the next steps are? Their email is not showing up on my blocked list, so I don't understand how this could have happened. Who handles the suppression list if it is not Xfinity?