I try and click on the shop in each of the towns were you can buy pokeballs ultra balls etc. I move my Ultra Balls to any place in my inventory but when I click they are automatically move to my hand. So every time I click they are thrown and I cant get them back. And when I tried to switch the u balls with another item the item disappeared and I lost a whole stack of revives and more than a stack of Pink healing potions ( I forgot name ) 01/21/18 8:20 - 8:23 AM G1 S1 file//CUsers/Mark/Videos/Captures/Minecraft%201.12.1%201_21_2018%208_23_43%20AM.mp4 IGN: ( CANNEDCHIPS )
This happens to me too and I find the best thing to do is relog and join the server again. Hope this helps!