Not sure if they have resolved your issue or what error messages you are receiving. However if they have not fixed your issue and the watch is showing in your account as if it is activated, request that they delete it from the system. Afterward, go back into the system and attempt to re-pair it to the cellular. It should work.
I'm sorry you're experiencing these issues. I went through all of that as well having to speak with the different tiers and managers with no call back. It was so frustating. I would attempt the method that I gave you as it seems to have been a common issue with most of the cellular phone companies (ATT, Verizon & T-Mobile) when they first brought these watches on board. I googled things to remedy the situation and saw that it worked. I believe that if you have it deleted from your account by a customer service agent and then you manually re add it again by starting the pairing and adding cellular process again, your issue will be resolved just as mine was. I know it is a headache as I had to go through 2 different agents because the first wouldn't delete my watch when I requested LOL. However, I have been using my watch for a week now with no issues. Once you get past that roadblock, things should go smoothly.
My apologies for the inconvenience you are experiencing. When you get a chance, reach out to me via private message by clicking on my name ComcastChrisL, and from my profile page click on the blue 'send a message' button.
In your private reply, please include your first and last name, the complete service address, the mobile number, and the last 4 digits of the card on file.
Once I access and authenticate the account, I'll look into the status of the situation and reach back out to you.