OT > A4 > OB > no more pattern pattern program change?

Hi everybody !

I’m working normaly with the OT as a master, sending clock Program change and note to the A4 but when I put the A4 on OB mode the A4 dont work anymore as receving program change and clocK…
the problem is that my ableton dont send midi to A4 so I did not understand why it is reacting like that.
I send clock to ableton with A4 midi thru normaly…

If someone can help me…
Thanks !