I have the same problem only with me the Hadset erkant as a screen, i. Although I have a picture but just from my laptop Bildschim. I have tried it with my brother and there it goes, despite the fact that he has a GTX 1050 and I have a GTX 1050ti. In the Oculus Setup the headset is shown but e is said that it is not connected to HDMI. Can I handle this problem with a HDMI to USB adapter?
That with the adapter forget fast again, that certainly does not work.
Change maybe the connection, renew the drivers of your graphics card. Is the Rift new? Again, the cable may be broken, etc. Avoid adapters of any kind.
So I reinstalled the drivers, updated and I only have one HDMI port.
But thanks anyway.