I was attempting to add two series 6 watches (one for a family member) to an iPhone 11 and while removing the watch app resolved this issue for the first watch, I couldn’t recreate this solution to add the second without unpairing the original watch. Below are listed the steps which finally resolved this issue for me: Make sure both devices are fully charged and connected to power Reset iPhone (for iPhones without home button - volume up, volume down, side button) Hard reset watch (press crown until option to reset appears) Turn on Airplane Mode for iPhone Ensure WiFi (2.4 GHz) and Bluetooth are on Manually pair watch This should resolve cases where Apple Watch requires an update prior to being paired. Hope this helps!