Unable to pair and update apple watch after carrying out a reset.
I reset my series 4 gps watch about 8 months ago after selling my iPhone and I've never used it since, until recently when I decided to sell it. I wanted to make sure it still worked so I tried to pair it as a family member to my wife's iPhone X. After around 30 seconds into the pairing process I get a message on the iPhone stating that the watch needs an update and must be "gps+cellular" to be able to update to iOS 7 and above! - then after a few seconds the phone goes through the process of unpairing the watch, and that's it - I can't get any further than this each time I try! Can anyone help please.