The Roblox error 500 can be one of the indicators of an on-going server problem so what you have to do is to check the game’s server status.

If a quick refresh did not address the Roblox HTTP error 503 service unavailable, your next move is to close and restart the web browser. Fix #3: Check Roblox server status.

"Roblox" outage May 2022 is still unfixed. Is this a normal system issue, or is the server hacked? Here's what developers announced.