No RC input in Mission Planner

I have a FrSky x8r connected from its SBUS port to the RCIN of my Pixhawk mini, but when I connect to the Pixhawk on mission planner, I’m not seeing any RC input in the Radio Calibration screen. The receiver and transmitter are bound and working, and the really strange part is I had all this set up a few months ago. I haven’t changed anything, so I thought it was perhaps a firmware issue, so I upgraded the firmware on the pixhawk as well as downloading the newest version of mission planner. I have tried every suggestion on all similar posts to mine. Is there any way of diagnosing what the issue could be? I only have one receiver and pixhawk. Thanks!