The Subscriptions feed error message is resolved for almost everyone. If you're still seeing it, know that it will be fixed soon – thanks for your continued patience! You can follow along here for any additional updates: https://yt.be/help/CBxM https://twitter.com/TeamYouTube/status/1119013035580878848 …
When a channel or account is suspended, you'll receive an email with more details about the reason. If you think it happened in error, you can always appeal. Also, here's more info about account terminations, including why it can happen: https://yt.be/help/WX8p . Hope this helps.