Okay, I have this purple potion bottle, it fills up both health and mana. I have used it twice. It is now full again, but I can't use it because the cork for the top of the bottle is missing. Can I get another cork for the potion bottle? Who would I get it from?
Sounds like you filled it back up playing Mini Games and it's not quite full. Rather than going to the expense of refilling them at Hilda Brewer, spend a few minutes playing a mini game and that should fill it enough that it needs to be corked. Once it's corked, you can use it.