It’s hard to nail this down. The tips of the leaf looks like it was burnt at one point. Probably due to a period where the medium dried out too much. Never let the medium dry out completely as this will cause nutrient burns to happen.
On the other hand I also see every tip on the sides of the leaves also starting to appear a slight bit yellow. Which makes be lean into a little bit of a Potassium deficiency as well.
Are you feeding a bloom booster, perhaps increase that dose by 10% on your next two waterings.
I hope this helps.