Make sure you're doing the following

• [Yes] You're using the latest build for your server version
• [Yes] This isn't an issue caused by another plugin
• [Yes] You've checked for duplicate issues
• [Yes] You didn't use /reload

Describe the question
I am using this sign gui method in 1.18.2 and for some reason the PacketTileEntityData#getNbtModifier returns null. I would like to know why is it returning null and how can I fix the problem.

API method(s) used
List what API method(s) you're using

Error
https://paste.helpch.at/kuruhovapa.rb