contact corporate for complaint

I could not find a way in this forum to contact corporate about a complaint. The only thing it confirmed is how many people are in the same boat as me with what seems like hundreds of complaints and no resolution.

I chatted with customer service in July about my internet service. I was told the new plan included an ipad and I just had to pay for new plan activation - I didn't need an ipad but they said it was included as part of the plan. Move forward 2 months to September I get 2 charges on my credit card, internet and xfinity mobile, I dipute mobile charge with my cc company since I don't recognize/authorize. Earlier this month I chatted with xfinity support and was bounced around to like 6-7 differnet people on chat, try to call and speak to an agent and can't get somone live. I decide to physically go to xfinity store but they can't help so put me live with an agent at the store (on the screen) and that agent can't do anything either. Plan was never activated and I can't return un used ipad and they tell me I have to pay for the device (double what it retails) because the return period closed in July. So I get tricked into a plan I don't want and have to pay double. I can't believe a company can do this to you and all you get is a 'sorry' nothing we can do and you have a contract you can't get out of even if you get tricked into it. And I guess they have no corporate office that is even looking into this practices that should be illegal.