Hi there and welcome
Can you for just during the upgrade, disable your Anti Virus program.
Then run the upgrade and if it is then able to complete, then re-enable it again.
It can interfere with the upgrade process.
I can also do these steps for you, and have made a request via Additional Services. This is optional, and if you choose to do this, I can, with your permission, remote into your computer while you watch and do all these steps (and deal with any problems that arise during them) for you. Or if you do not choose to take this service, we can continue here. This is no problem at all. Just let me know please.
Else let me know the results please.