Xfinity support

I would like you to ship to me a new Xfinity box capable of 4K as we have a new television set. We have been with Xfinity for a long time and getting to the Boulder office ( the closest) is difficult for us. We would also like to return our old box we have for a long time by mail. We would like all the included remotes and we would like to know if our two other smaller boxes are going to work with this new Main box. Also, we would like to know if our plan with Xfinity will have 4K running through it. We have been trying for hours to get this information via the Xfinity assistant and chat and it’s been a nightmare. My husband is ready to cancel. I would like to keep our service. Can you help?

• 4K boxes (X1 4K: XG1v4 / Xi6)

We have looked for this direct message option and cannot find it