Try updating the firmware through the Chasing app. If that doesn’t work, ensure no interference and test with a different device to rule out connection issues.
I’ve seen others recommend custom solutions like using FPV receivers and goggles, but for cheaper VR setups, finding an app to split the screen might take some digging.
If it's a wire break, soldering is your fix. For connectors, make sure you find the right pinout. A good electronics or computer repair shop should handle that with ease.