Option to back up iPhone to Mac is greyed out
I want to back up my iPhone XR to my Mac - when the phone is plugged in and shows in the Finder, the option to back up to my Mac is greyed out. I am on a strong wifi system and my Mac is connected to a power source so I don't know why this keeps happening. I have tried unplugging the phone and plugging it back in but that doesn't resolve the issue. All my devices are up to date with the latest operating systems.
iPhone XR, iOS 13