XfinityStream DVRrewind doesn't work.

Xfinity Stream app DVR programs won't rewind. When I  use the rewind button, it restarts the program. This started Saturday. Xfinity says there was an update. They also say that my LG ThinQ's firmware is the issue and not their software. I called LG. They ran all of the diagnostics on my TV and said the TV and firmware are working fine and are compatible with Xfinity Stream. They said the problem is in the Xfinity Streaming App software and Xfinity needs to fix it.