How can I re connect my Apple Watch to my iPhone?

So yesterday, I had forgotten my new password to my phone, it became disabled and I had restore it through iTunes and iCloud. Total pain in the a**. So I got my phone back, but a lot of things were missing and out dated and my watch wasn't connected to my phone. The last backup was Sep 2016 and I got my watch in Sep 2017. The activity app connected to my watch isn't there. My watch still tracks activity and is connected to my iCloud as I just got it to play a sound using find my iPhone. Now i just have a watch that's not connected to my phone, but still recording stuff and I just do not know how to repair it. I went to the watch app on the phone, but it just shows pair watch, but I can't.

Your watch thinks it's paired to the 'old' phone before the reset. Erasing it back to factory settings should take care of that:

1. On your Apple Watch, tap Settings > General > Reset > Erase All Content and Settings.
2. For Apple Watch Series 3 (GPS + Cellular), choose to keep or remove your cellular plan.
3. Tap Erase All to confirm. This resets your Apple Watch to the factory settings.

"Unpair your Apple Watch and iPhone"