Can’t import videos. Dynamic server issue.

Lightroom classic can't import anymore my videos on my Mac.
I create a catalogue only for my videos just to organize them by date/fps/etc. After about 4.000 files correctly imported now there is no way to go on. When i sync the folder where i have my videos Lightroom freeze and give me the dynamic server error.

I tried to exit and end the two dynamic processes

I deleted the "dynamic" folders everywhere 

I increased the cache of the catalogue.

No way. I had one lucky success just once when i first tried the exit from LG and the dynamic processes. Than stopped again.