Check Roblox Settings: Make sure that the Multi Game Instance feature is enabled in the Roblox settings. Sometimes, updates or changes to the app's settings can inadvertently disable certain features.

Update Graphics Drivers: Ensure that your graphics drivers are up to date. Outdated or incompatible graphics drivers can sometimes cause issues with gaming applications.

Disable Third-Party Software: Some third-party software, such as overlays or performance-enhancing utilities, can interfere with Roblox and other gaming applications. Try temporarily disabling any third-party software running in the background to see if it resolves the issue.

Run Roblox as Administrator: Right-click on the Roblox shortcut or executable file and select "Run as administrator." Running the application with administrative privileges can sometimes resolve compatibility issues.