If you have bought an Apple Watch that is still linked to the previous owner's Apple ID, you will not be able to use it until you remove the old Apple ID. There are two ways to do this:
- Contact the previous owner and ask them to remove their Apple ID from the watch. This is the best option, as it will allow you to keep all of the data on the watch.
- If you cannot contact the previous owner, you can erase the watch and start over. This will remove all of the data on the watch, including the previous owner's Apple ID. To erase the watch, follow these steps:
- Put the watch in pairing mode.
- On your iPhone, open the Watch app.
- Tap My Watch.
- Tap All Watches.
- Tap the name of the watch you want to erase.
- Tap Unpair Apple Watch.
- Tap Unpair.
- Tap Erase All Content and Settings.
- Enter your passcode if prompted.
- Tap Erase All.
Once the watch has been erased, you can start pairing it with your iPhone.
Here are some additional things to keep in mind:
- If the watch has a cellular plan, you will need to contact the carrier to cancel the plan.
- If the watch is still under warranty, you may be able to get help from Apple to remove the previous owner's Apple ID.
I hope this helps!