I have the same problem since the last update. I use android system, I've tried everything and I couldn't solve it. I called Eventide's assistance and it was unable to solve the problem. I try to connect via Bluetooth and it presents the same error that it has presented to everyone, I hope they solve it now. Following are prints of what happens. And the error presented itself after updating, it is not possible that it is a hardware defect.
Could you try using H9 Control on one of your other devices like tablets or desktops? So we may figure out if it is yout H9's problem or your phone's.