Middle click Logitech mx3 not recognised on macbook air (but works on Imac)

I'm using the logitech mx3 mouse. I've been using it succesfully on my Imac, and it's functioning on tha macbook air also, but when I want to create a new trigger on the macbook, the middle mouse button is regocnised only as left click.

Am I missing a specific setting?

Device information:

  • iMac (Retina 5K, 27-inch, 2020)

  • MacOs Catalina 10.15.7

  • BTT 3.570

  • MacBook Air emphasized text(M1, 2020)

  • MacOs 11.4

  • BTT 3.570 & 3.579

I've tried with old and new versions of btt, but ca. that didn't help

Hope I'm overlooking something, thanks!

Do you have the logitech software installed on one of the machines but not on the other?

The logitech options software is installed on both devices

Then you should check whether the middle click button has the middle click option assigned in the logitech options software, most likely some setting is wrong there.

That's also configured the same on both devices unfortunately