Telegram - CAN'T MESSAGE GROUPS! Anyone else had this problem?

I've been using Telegram on both iPhone SE and Mac OSX. Actively in the BitShares as well as few other Crypto channels you may also know me there..

I can send/receive with normal contacts, it is only to supergroups or public chats I'm having the errors.

The issue did happen before and some quick fix with notifications seemed to do the job. Now no matter what I do, reset, reinstall, leave and rejoin groups, nothing is working!

I can see everything going on just grand - I just can't respond or send any of my own messages. That's why if you've wondered where I got to now you know.

I even tried telegram web. This is the error I get there:

ANY IDEAS WELCOMED!!!