Error

[akva5]

java.lang.IllegalArgumentException: Failed to serialize ItemStack
at BLib.jar//org.by1337.blib.nms.V1_21_6.inventory.ItemStackSerializeV1216.serialize(ItemStackSerializeV1216.java:64)
at BAuction.jar//org.by1337.bauction.db.kernel.SellItem.serializeItemStack(SellItem.java:224)
at BAuction.jar//org.by1337.bauction.db.kernel.FileDataBase.validateAndRemoveItem(FileDataBase.java:359)
at BAuction.jar//org.by1337.bauction.action.BuyItemCountProcess.run(BuyItemCountProcess.java:55)
at BAuction.jar//org.by1337.bauction.bmenu.menu.Menu.lambda$static$23(Menu.java:424)
at BLib.jar//org.by1337.blib.command.CommandExecutor.execute(CommandExecutor.java:21)
at BLib.jar//org.by1337.blib.command.Command.process(Command.java:158)
at BLib.jar//org.by1337.blib.command.Command.process(Command.java:127)
at BLib.jar//org.by1337.blib.command.Command.process(Command.java:110)
at BAuction.jar//org.by1337.bauction.bmenu.menu.Menu.runCommands(Menu.java:123)
at BAuction.jar//org.by1337.bauction.bmenu.menu.Menu.onClick(Menu.java:149)
at BAuction.jar//org.by1337.bauction.bmenu.menu.AsyncClickListener.lambda$doClick$0(AsyncClickListener.java:152)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
at java.base/java.lang.Thread.run(Thread.java:1583)
Caused by: java.lang.IllegalStateException: Value must be within range [1;99]: 0; Item must not be minecraft:air
at com.mojang.serialization.DataResult$Error.getOrThrow(DataResult.java:287)
at com.mojang.serialization.DataResult.getOrThrow(DataResult.java:81)
at BLib.jar//org.by1337.blib.nms.V1_21_6.inventory.ItemStackSerializeV1216.save(ItemStackSerializeV1216.java:95)
at BLib.jar//org.by1337.blib.nms.V1_21_6.inventory.ItemStackSerializeV1216.serialize(ItemStackSerializeV1216.java:60)
... 14 more