If you've got an M3U in the form:
http://server:port/get.php ?......
then try using Smarters Pro. Much nicer.
Would be better if you gave a bit more info, so just to ask, what do you have TM (and/or other players) installed on?
Providers do not have 100% uptime. Sometimes they crash, have maintenance or whatever.
It’s a grey (ok, let’s just call it - Black) market. Don’t expect miracles.
Edit: ah, it’s the app not the stream. Hm.
It’s a relatively new app I’ve heard some good some bad but the overall impression suggests it’s very buggy. Maybe in a year it’ll get better
Did you ask in /r/tivimate?