[SOLVED] DataManipulator not working fine

Hello there! I created my own DataManipulator for a ShopSystem in Sponge.
It works fine if i create a Sign and so on, but if i Restart the Server, they doesnt work anymore. Heres my Code hastebin .
I offer These to a Sign (TileEntity) on SignChangeEvent. That works great but after Restart if i click on it, the Debug (printing the Values) in my Plugin isnt working.

Try using some of the type-specific methods in buildContent(). For example, getObject(query, UUID.class), getInt(query), getFloat(query), and getCatalogType(query). You shouldn’t have to make any casts in that method.

After a few Hours i found the mistake.