Thunderbolt Controller 1575 Error Code 45

Has anybody figured out how to keep this controller active after having this problem? I can update the firmware but the controller only stays active momentarily before I get this error (code45). I have all the latest drivers, adjusted  the BIOS settings... nothing seems to work after exhaustive search over months. The port works fine for usb-c, but thunderbolt cables are not even recognized due to this error. How do you fix it? Thanks for any solutions that have worked for you....!