Sonoff R3 Dual - blinds move only some cm

Hi,
I’m searching for some advice.

I have a motorized blind commanded by a 3 way rocker switch.
I’m trying to install a Sonoff R3 Dual on it.

The manual calibration goes well apparently.

But then when I click “Open” or “Close” in the app, the blind moves only a few cm’s ~5%.
The curios thing is that the “openness slider” is always correct.
It knows that the blind is 85% open…
But when I click close it stops at 80%.

Do you have any suggestion or previous experience on this?

Thank you