When you click on one of the blank spaces where your photos should be, does one of your photos open? If so, it might just be an issue with the thumbnails not loading, rather than your photos being missing.
Could you let us know what version of Lightroom you're using? Also, please check if there are any updates available for your drivers.
If that doesn't help, could you try resetting your Lightroom preferences? Just make sure to back up any preferences you want to keep. To reset, hold down [Alt] + [Shift] while opening Lightroom. Overwrite the Preferences when prompted by the dialog and then restart Lightroom.
Thanks a bunch!
Alek
*(If you mention me with an @, like @Aleke, I’ll get a notification and can respond faster.)*
If you're synced to the cloud, you shouldn't lose any of your presets when resetting your preferences. You can check your sync status by visiting https://adobe.ly/42LJRUh and seeing if your photos, edits, and presets are there.
Hope this helps!
Alek
*(If you mention me with an @, like @Aleke, I’ll get a notification and can respond faster.)*