Roblox' recent updates reportedly added an anti-cheat that is blocking game capture from working.
Because of this, any fix to getting game capture working will have to come from either Roblox or their anti-cheat provider.
You will need to use window capture
Here it is, can you help?Please post a log with your issue! Here's how...
OBS Studio creates a log file each time you run it which contains very useful diagnostic information. Without a log file, it's much harder for any support volunteers to figure out problems and your post may be ignored. To upload a log file, go to the Help menu > Log Files > Upload Last Log...obsproject.com
thanks broThat's an image, not the actual log file.
Follow directions and recommendations you see on the analyzer. After you finish fixing all that, do a new test and post the actual log file, not an image