
As you have noticed, Repair Now often fails to work.
Instead, run an Online Repair from Windows Settings. See https://support.microsoft.com/en-us/office/repair-an-office-application-7821d4b6-7c1d-4205-aa0e-a6b40c5bb88b .
Note that you usually have to reinstall Office as part of the Online Repair. Before you begin, make sure that you can access your account and that Office is associated with it.