Hi! Happy Birthday to Oliver!!
I have never experienced this, so sorry I have no feedback, but I would be interested in seeing a picture if you have any?
My parakeet has some fungal issues on his beak after he damaged his beak some. Vet prescribed antifungal for 10 days, and there has been no recurrence since (4 years now). But your birds cere thing sounds quite different than that.
Wishing you and your bird the best of health!