i made a chest GUI but if you click on the immovable tiles with an item it deletes that item, i want to fix it so people don't lose special items.
btw its a custom crafting grid GUI
Sounds like you forgot your read/ write NBT methods in your TileEntity* class.
* Updated due to wrong class containing read/ write NBT.
In your Tile Entity class for interactive items, such as crafting tables/ chests/ furnaces, there is a readFromNBT/ writeToNBT method that remembers when items are put in, and taken out.