iCloud not syncing with Photo App
I have a MacBook Air 2007. Running the latest BirSur fully updated.
maybe about two months ago my photo library got a little muddled io it ended up with three photo libraries.
Upon my stupid non tech guy I decided to delete the one library and there it all started to get worse.
Now I have one library but can't get it to sync with iCloud to get all the photos into the photo app.I have a iPad and iPhone 11 them both are syncing with iCloud photos.
My question is what can I do to get the photo App Library to sync with iCloud there are approx 5000 photos there.
Help please can I make a new photo library to sync with the iCloud on this MacBook air
Help please.A friend suggested a reset of the MacBook that sound a bit drastic or maybe take it to the apple store for help.
Any suggestions Please.
David pulling my hair out.
ps.If I log int my iCloud in another item all the photos are there.
Many Thanks.