i havent loged in for few months...
after reading your post I've been logging into my account and everything is fine. I have not logged into my account for more than 6 months and my account is verified and from what I have seen it has not been blocked. so I think the reason your account has been blocked should be related to your country or the documents you have submitted to verify your account
Probably this might be the reason behind all this. From last year Bittrex was strongly forcing users to pass KYC and i remember they disabled accounts from some specific banned countries. It seems that they did it again and you are one of them from banned country, it is really unethical and nonprofessional that they disabled account without any prior notice.