It's hard to know where to start unless we know some details of what led up to the current status.
Was there ever a time when the aircraft and controller were properly bound? If so, what happened that required a re-bind?
The binding process has several steps. If we knew more about what steps you are doing, what you are seeing in response to the steps, and at which step things seem to go wrong, it may help us provide information.
This video is for an H-Plus, but I believe the H-3 binding process is the same. Please compare it to what you see and let us know where things don't work: