0. ALWAYS PROVIDE INFORMATION ABOUT MODLOADER (Fabric / Forge) AND MOD VERSION (For Example 1.19.2-8.2.10)
   Fabric 1.16.5 travelers-backpack-1.16.5-5.4.26

1. Describe the bug
   When you press the sort button, the server crashes when sorting the backpack

2. Write steps to reproduce the bug
   1.Open the backpack
   2.Put items
   3.Press the sort button

3. What is expected behaviour
   https://pastebin.com/791ydxWg

4. Screenshots (If applicable)
   

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