Sequoia 18.2 not seeing iPhone backup on "manage backups" under phone tab

Desperately seeking help with syncing an iPhone back up stored on my Mac. New iPhone, last iPhone was stolen at a bar. I backed up my last iPhone to my Mac running Sequoia. The back up is under the folder \~/Library/Application Support/MobileSync/Backup. I see the back up of 129GB present and synced properly on the my last back up date. But when I connect the new phone to my computer, the "manage backup" tab is empty. Also the "restore backup" tab is greyed out. I'm not sure why Finder is not seeing or linking the backup folder that is present in the default MobileSync/Backup folder on my Mac. I saw another post on here that it might have to do with permissions of the folder, but I am the administrator for the computer and the folder is set to "read/write" Has anyone encountered this problem before? Is there a way to tell finder to search the MobileSync folder to get the back up of my previous phone installed. I am desperate for any help you might know, since the Genius Bar at Apple did not know how to fix this and are telling me to call corporate apple support for a possible fix. Your help is appreciated!!! Thanks