There seem to be a problem with iOS 13 and above. I almost sent back a phone I bought recently on Amazon as I could not pair it with my Apple SE2020 with iOS14.4. If you encounter this problem, the solution is to sign out of iCloud on your phone (Settingsselect your profilescroll to the bottom and sign out. NB: You will need all your account verification in order to sign out). Once you have signed out, reconnect the phone to your wifi. Next, reset the watch (switch the power offswitch power onwhen the logo appear, hold the power button until you see erase setting, erase the setting accordinglyrestart the watch). Restart the pairing process and you will be good to go. Remember to sign back to iCloud. You will NOT lose any data on your phone