You probably reinstalled some part of Office too many times. Just call microsoft help line and they will walk you through resetting it once they verify your license. It takes a few minutes. There has never been a charge for this in the past.
Well “myPhone support” wanted $109 for one time fix, or $199 for a year of support. I called the 8XX number another poster offered up.
I told them no - that I have been an Office customer for 20 years, and have always paid for upgrades and it was their problem.
We parted ways.