Problem/Bug Can't place blocks from 1.13 to 1.16

Hi! I've set up a bukkit server and I can't place blocks if they are from the four latest versions of minecraft. Only if I place them via "WorldEdit". The server is updated to 1.16 so I don't understand why it does'nt work. Pls help!

 

No my spawn is in another world! Can it be something with my plugins?

 

Okey I will try that

It was'nt the problem. I tried to set the spawn 1000 of blocks from where I was building but it did not work

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

@timtower
Nope! the block is visible in maybe 1sec and then disappears. But no message

 

So! I don't know if you can see it but i've done it.
https://pastebin.com/s9SMUVcc

 

Ok thanks!