Error my item not save and i have code error

Hello i have paid one source i think to a leecher because don’t answer me.
I have setup the base and all working good but when i’m buy item from shop is not save…
And when i’m join the server i have this error : !

if you can help me please its very cool.
i’m novice and i’m learn but is difficult ! Thanks for your help and sorry for my bad english.

One of the most important things you should be able to do when you’re running a server, is being able to read error messages.

As your error message litteraly says:
You’re trying to insert a duplicate entry in your database, which is not possible.

Search for duplicated entries in your user_inventory table and delete them.