Items dissapear in duels?

Your username: Snakehammer19

In which minigame/server does the bug occur: KitPVP

Detailed description of bug: Alright, so before a duel match begins, there will sometimes be items that disappear once it starts. An example would be when doing a Potion (NoDebuff) duel with a player. Before the match begins, one person may lose some of their potions without even fully drinking them.
I was playing a few duels when I discovered this. My fire resistance potion had disappeared right as the match began. I did not have the effects of fire resistance on either which caused me to constantly take damage from the fire aspect. I honestly do not understand why it happened. Hopefully, this will shed some light to the issue.

 

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At that part, I drank the potions a little bit before and after the battle began. They did not appear to give me the effects or show in the PotionHUD mod I had on. Both the pots had disappeared without giving me the effects.