I've had my VR mappings randomly up and disappear on me a few times for no apparent reason. Everything would be unassigned. Once you're in VR the game creates another set of files it uses in VR. What I did to fix it was to copy the regular map files, delete the VR ones and rename the copies to the VR file names one at a time. That was the first couple of times thinking it was some oddball problem. Now I've made a backup saved to the desktop in case it happened again - - - it did!
You could do this right off and save a lot of time setting up your controls if you want them to be the same as you use on a monitor.
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