Any ideas what this could be? It's only on this flower

Hey AD is this the only spot? It looks to be nute burn because it’s at the top only did you increase the feed or did this happen after your last feeding? Could just be walking the line and this particular plant might be a slight bit more sensitive

I am just throwing out a possibility but could this cola be getting too close to the light?

I thought maybe the light was too close so I raised it some. Haven't had to feed for a bit because I premixed my soil way before adding in the plants and they have been growing in those pots for quite some time now

I agree with Hulkster, could be a hot spot in the mix .