I was avidly reading IntelSlav Z etc. at Telegram and my phone available memory gradually disappeared until my phone wouldn't function.
It turns out Telegram defaults to storing media on your phone. It is very easy to fix. Instructions are here:
https://www.guidingtech.com/top-ways-to-free-up-space-in-telegram/
I've tried the fixes cuz I would like to get on telegram, but I always still had the problem
It works like a charm. Super easy to fix. I don't know why you would till have the problem. Just follow the instructions in the link.