IPad: Bias FX and Bias Amp2 issue with Harley Benton MP500

[o_oliviero]

Hello...
I can’t understand what’s happening.
I have Bias FX snd Bias Amp2 for iPad. I also have JamUp for iPad and Bias FX2 Elite and Bias Amp 2 for Pc (windows 10)
I recently purchased Harley Benton MP 500 to play live but it seems it cannot work with Bias FX and Amp2 for iPad.
I mean: if i connect that MIDI pedalboard to pc and run Bias FX 2 (or Amp 2 for windows) everything is fine and it works correctly.
But I have a strange behaviour with iPad versions: JamUp and H.B. MP500 together are OK (if I play guitar, i can hear it LOL) but if I try to use Bias Fx or Bias amp it seems it does not receive any signal!!! (If I strum my guitar the input bar at the bottom left of the apps doesn’t move!!! And I cannot hear anything, of course...)
Other strange behaviour: bias FX and H.B. MP500 work perfectly if I connect my iPhone (I have Bias FX in my iPhone too)
Where am I wrong with my iPad apps?? What am I forgetting???

(Edit: obviously, microphone is activated in iPad settings for both apps Bias FX and Amp... and in audio settings “left channel” is checked, with my guitar plugged into L channel)