Thanks for confirming. Can you tell me the software version you're running too? This can be found by pressing Settings/ Menu on your remote and going to Support > About TV.
07-04-2020 03:50 PM - last edited 07-04-2020 03:52 PM
I can confirm that the UE50RU7100KXXU doesn't support PVR - hence why neither of the drives are working. From that model's product webpage specs:
Apparently, for R-series TVs PVR capability starts from RU7400 upwards.