I kept using the vamp but it won't work. I relogged and tried again, didn't work.

Be sure that you don't use it in the first 10 seconds of a round as none of the consumables are working then.

I tried again after the first 10 seconds and it still didn't work.

Were you in the hole/dead?

I was in survivor and alive

You can't equipt the vampire costume on a survivor room... To prevent the confusion on vampire maps. U can use the skin on a normal room and go back to survivor.

Ah okay