Legacy BBOS devices still require a BIS data plan from the carrier. BB10 devices do not use BIS. On some carriers, there are reports that having BIS in place for a BB10 account causes no issues. On other carriers, there are reports that having BIS in place for BB10 causes the BB10 device to not function for data services at all. It varies. But, BB10 devices definitely do not use BIS data plans.
Occam's Razor nearly always applies when troubleshooting technology issues!
If anyone has been helpful to you, please show your appreciation by clicking the button inside of their post. Please click here and read, along with the threads to which it links, for helpful information to guide you as you proceed. I always recommend that you treat your BlackBerry like any other computing device, including using a regular backup schedule...click here for an article with instructions.