If you connect the Helix to your computer via USB and use a MIDI monitor app, you should be able to confirm that it is sending PC changes (or not). https://www.snoize.com/MIDIMonitor/
You could also try a reset on the H9, you should backup your presets first. To restore Factory Presets and all System settings, power up the H9 while simultaneously pressing the Right Footswitch and the big Knob until [INITIA] is displayed
