Fatal error in adding a list

Situation
I want to add a list which is the type of codes but I have a fatal error
Fatal error : Uncaught TypeError: Unsupported operand types: string + int in C:\xampp\htdocs\openemr\interface\super\edit_list.php:76 Stack trace: #0 {main} thrown in C:\xampp\htdocs\openemr\interface\super\edit_list.php on line 76

OpenEMR Version
I’m using OpenEMR version 6

Browser:
I’m using: Microsoft Edge

Operating System
I’m using: Windows

Logs
Did you check the logs?
Was there anything pertinent in them?
Please paste them here (surround with three backticks (```) for readability.
You can also turn on User Debugging under Administration->Globals->Logging User Debugging Options=>All

Can you post a screen shot of what you are trying to do, right before you get an error?

This was fixed in an earlier version 6.0.0 patch.