Witchery Familiar - Fire immunity

[Poseidon5001]

Hello all, I am in the process of making a modpack. I noticed something strange with witchery
Binding a cat familiar seems to grant the player fire immunity, instead of just the cat. I get the damage tick sounds, and the effect on my player, but my hearts do not go down for fire
Same thing applies to poison. If I dismiss the familiar, same thing. I must actually reset my file in playerdata of the world to take fire and poison damage again.

Anyone have a solution? This is game breaking as it removes one of vampire's two weaknesses.
Any help would be appreciated ASAP.
Thanks!
daPoseidonGuy