Bleb that won't go away after weaning?

Hey all. I have a stubborn bleb that won't go away despite having weaned my daughter a couple of months ago (at 21m! So proud we made it that far). I've popped it a couple of times now and but it keeps coming back.

It's not painful, I don't feel any lumps or blocked ducts, but I'm pregnant and due with #2 in May so I'd like to try and take care of this before baby arrives. I've tried a bunch of things already but I'm totally open to suggestion. I'll be asking my midwife about this at my appointment next week but thought I'd try here first.

Anyone have any advice or suggestions on how to tackle this??