I don’t have a fungicide.Try spraying with fungicide it looks like it might heal itself so just wait and see what happens.
I am not sure, but this is how the flowers look.How far along are you in flower?
A cinnamon paste might work....I don’t have a fungicide.![]()
I would carefully cut that part out with a razor, you don't want spores of whatever it is flying loose, then wrap it with a silicone bandage or silicone tape, and let it heal.