When i want to throw something out it reapears.

Whilst I was getting rid of a block in the creative inventory it reappeared in my inventory. I tried again but by pressing 'Q' to throw it into lava and as soon as it burned it reappeared again. The thing was I was getting 2 stacks of items back each time.

I figured it was some sort of duplication glitch clearly but until that glitch is fixed I am going to try and resist playing this version of Minecraft otherwise in my survival games I would have billions of diamonds right now.

Hopefully you can fix it as soon as possible Mojang. Thanks for reading.