$30 Discount for Xfinity Internet With Getting the Xfinity Mobile has been a big mess

I got a new internet service in April for which I am paying $25 per month for 24 months ($35 monthly bill being $25 due to $10 automatic payments and Paperless Billing discount).

I called in May in regards to some charges for non-returned equipment. While those were sorted out, the Xfinity rep talked me into getting the Xfinity Mobile, telling me that I would get a $30 discount on my internet each month and could make my total internet bill for which I am currently paying will go down to $0. And overall I will be paying less with just $15 plus taxes for the mobile service.

I called back in June to inquire as I didn't see the discount and I was told that it takes a month to reflect and as part of the conversation, I was told that the $30 discount is before the $10 autopay discount so technically my bill would be $5 per month instead of $25. I asked it to be investigated and see why I was promised a $0 internet bill going forward. I was told that someone will get back to me in couple of weeks but didn't hear back.

I called again now since my internet bill was still $25 with no discount and I was told that there is no discount on my account and the max discount I will be offered is a $10 discount per month as existing cusotmer and they can't provide me with the $30 discount which was offered to me as a new customer. 

The amount of time I had spent on dealing with this was so much that I regretted of getting the Xfinity Mobile. I almost feel like cancelling the Xfinity Mobile service (because with the incorrect internet bills my monthly cost is higher than before) since I do not really need it. But I got a so-called free phone when signing for the mobile service (but the cost of the phone is credited each month over 24 months) and if I cancel the service I would then have to pay for the remainder of the cost of the phone. This would put me in jeopardy.

Just so frustrated. Previously I would highly recommend friends to get the Xfinity Mobile to enjoy the $30 discount. But I will no longer do that because the billing is so screwed up. I would probably even tell people to get away from it because it's just too much trouble to go through getting billing corrected.