Hello,
Sorry to hear you are having issues. Need more information.

1. You on Windows 7,8,10 or 11? Also need to know its full version number. Use Winver.exe to get those number.
2. You are talking about Start11 or Start10? Also need its version please.
3. Details on your monitors resolutions and scaling, 100%,125% etc.

Thanks
Basj,
Stardock Community Assistant.

On all 3 monitors?

Try this, uninstall Start11, reboot immediately, download and install Start11 v1.26 Beta, reboot again. And retest. But, if you're not comfortable in using betas you can try download again Start11 V1.25 and use that instead.

Thank you,

Basj,
Stardock Community Assistant

Please try purge and reinstall steps as mentioned here: [Link]. Just make sure to redownload the latest version from your account page. Reboot after the purge. Reinstall and reboot again after the installation. Retest and report back here.

Thank you,
Basj,
Stardock Community Assistant.