Hello all, I have modified an open source project (Universal Market) to work with a mysql database instead of sqlite, and the script is now sucesfully writing the NBT data to my database, however it is throwing an error when I try to bring up the market menu in game.

 

Here is the error:

https://pastebin.com/nqxRUXVk

 

and here is the offending code:

https://gist.github.com/pdglobal/089b48b1ea0612a327b81488fed952b0

 

Please note I'm a total noob to making mods/plugins, could someone please point out what is going wrong here, and how to fix it to work with the latest version of minecraft?

Thanks, it's working now.