Us Att IPhone 6 , rsim 10, iOS 10

Good morning everyone , I’m from Mexico.
I have an iPhone 6, from us att. I put an rsim10 to use it with Nextel Mexico carrier….
It has been asking for activation on circles… it worked 10 minutes as a phone with no data and that’s it…

I been entering apples I’d and password and when it recognizes the SIM card it triggers the activation screen again. 🙁

Any help will be highly appreciated