enter time machine blank

Are you able to open the TM drive on the Desktop and view the folders for the various previous backups?

Hold down the Option key and click on the TM menu in the menu bar. Select "Browse Other Backup Disks…". Select the same disk you've always used and see if there's any change.

If that does't help boot into Safe Mode according to Start up your Mac in safe mode - Apple Support and test to see if the problem persists. Reboot normally and test again.

NOTE: Safe Mode boot can take up to nearly twice as long as a normal boot as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

I don't believe you can restore just a single entry. Like Mail you have to restore the entire lot for a given time.

You might be able to restore this folder to the desktop,

go thru it to find the contact you want and restore it by itself.

I have this same issue with the following conditions. 24" Mac, 16GB Memory, running OS 11.4. A Secondary display is a Samsung 225. If I turn off "Mission Control>Displays have their own space", I can get past the Blank Primary screen and see the Time Machine Folders stacked by time. However the secondary display goes blank. This is really not an acceptable solution since the Menu Bar does not follow the apps like safari to the secondary display in this configuration and obviously when in Time Machine you loose the entire second display. Need some help here from Apple.

FWIW you can make the user library permanently visible by going to your Home folder and then using the View ➙ Show View Options menu and then checking Show Library Folder in the resulting window: