Apple Watch update

My Apple Watch needed to be updated, so I tried to update it but told me that I needed to free up some space. I clicked on the option to free some and then the watch app wouldn’t switch tabs unless I updated the watch or factory reset. I clicked on factory reset so I could update it after I reset. I ended up having to leave home so I wasn’t connected to a stable wifi connection other than my cellular data. When I came back home and tried to start over, it doesn’t work! It stays on the “checking for updates” screen LOADING until my phone uses my cellular data and then it won’t let me update