I finally found it ! It works !!!
I finally figured out what to do and where my mistake was,
I will put the screenshots here for those who have the same question.
So, just checked if the sender is the server
or the client and then call the “possess” function
for each of them on the server !
I could never have understood this without
your help @Alekann01, @Aherys_ so thank you sooo much :))
