How to know if GTA online servers are down?
You can find information on any issues Rockstar Support is aware of by following @RockstarSupport on Twitter, which outlines when they’ve been resolved. Patch notes for GTA Online will also appear there, though unlike many other games, they are rarely taken offline for planned updates, as they are deployed directly into the live environment. Next thing is to check https://support.rockstargames.com/servicestatus, and if it all looks good, also check out Downdetector to see if other gamers are experiencing the same problem.
If everything else looks okay, there might be an issue with your account. You could’ve been banned for using GTA Cheats, or there might be some other reason either way at this point consider contacting Rockastar Customer support.