Horrible coverage

I'm on Business Mobile. Got a device payment plan February 6th. Apparently, after a week of TRYING to get it to work, it just won't. The coverage is not there. I have to go outside next to a sign to get any service. And OF COURSE Xfinity has no network extenders for mobile. So I called, trying to return the device. Apparently "buyer remorse" is set from the PURCHASE date. Even though it took a WEEK to get my device, that doesn't matter. It's the week before purchase date. AND doesn't matter that I contacted them BEFORE the deadline, with no response from them. No, none of that matters.

So I was like "fine, I'll keep paying but unlock the device." Nope. It SAYS I can on THEIR website I can do that if I still have Business Internet/Voice (which I do) but they want it paid off entirely and not in payments.

If they don't assist me, I'll be changing my internet and EVERYTHING else from them, too. I refuse to give them ANYMORE of my business.