Pitch Woobeling on fixed wing in ACRO mode

[samsab1]

Hello to the community
who can help me with my S800 which woobeling on the pitch axis in ACRO MODE); see the video here
https://www.facebook.com/100009352821454/videos/866817958897668?idorvanity=947623022106163. (watch from 30 seconds)
In manual mode, no wooble so no problem with the servo and the rods; the mechanical part of this wing is ok.
I don't know what to do.
usually, I start to adjust my plane with the autotune, and it's pretty well adjusted, for this S800 Reptile + matek f405 + inav 7.1.2, I can't get a good setting; above 50 km/h, the s800 woobles on the pitch axis.

thanks for your help