Question
I have the mod and all supporting mods downloaded (1.19.4 Forge) I can see the backpack in creative and spawn them but I am unable to open it, also when I try to craft them normally it does not work.

Did I make a mistake during the install?...

Everything seems to work fine for me on the latest version of Packed Up for 1.19.4.
Please use the 'Bug' template and provide version information and a description of what exactly is not working,