23,98 fps going out of sync

Hi,
I did a shoot last week in the US using my Zoom F8, and the camera was a Sony A7S II.
We did some test at home in 29,97fps and it worked fine.
Unfortunately, the camera operator decided, on day1, to shoot in 24fps. So I’ve set my Zoom F8 recorder to 23,98ND and my tentaclesync E to 23,98 FPS, set the audio level to MIC, waited for the led to go green and…
Once’s in Tentacle Studio everything is going out of sync…sometimes it is okay in the beginning but progressively goes out of sync.
It reads the Audio LTC of the camera but it has sometimes a 30minutes offset with my audio timecode…
The real framerate of the camera is 23,98 but it’s internal timecode is apparently 24fps.
What was my mistake? 23,97 instead of 24fps?
Why is everything going out of sync?
Thanks