Reconnecting missing files

You still haven't told us enough information to figure out what has happened.  

Where are your photos stored - specifically - and with what kind of folder organization? 

What work have you been doing over the past week that you do not want to lose?

Do you have any auto backups in the location I identified earlier?

And how was the Elements 2025 catalog created?  Was it converted from a prior version's catalog?  Or did you do a bulk import?

Where are your media files stored?

Where did you backup the catalog to?

Are any of your catalog files in stacks or version sets?

Have you allowed Elements to make an automatic backup of your catalog structure?  If so, the auto backup(s) will be found in the following folder:

C:\ProgramData\Adobe\Elements Organizer\Catalogs\_AutoBackup_

If you have a backup that is dated before the problem arose, go in to the folder and double-click on the catalog.pse25db file.

The backed up catalog should open.  Does it have the same problems with missing files?

Have you performed any file management tasks (move, delete or rename) outside of the Organizer?

When you select a missing file, where does the Organizer think it is? (This should be displayed in the reconnect dialog but you can also look in the Information panel under the Location link.  If the location is not fully displayed hover over it to see the full path.)  Does that give you any clue as to why the file is missing?

As @paulb74770752 suggests, you should search your computer to see where the file is actually stored.  (I recommend a free utility called Everything as a search engine.  It is a lot faster and more flexible than Windows File Explorer, in my experience.)

If this were me (and I use windows), as a starting place I'd check with File Manager to see if the files exist on my storage device.

I use internal storage, so my storage location is always the same. If you use external storage make sure it's plugged in and accessible.