HELPPP......Mould in Kush plant

I'm in my 3rd week of flowering.....currently growing some type of kush. Problem is, there is some browning in the tip of my main cola and this "browning/mould" is preventing my pistils from penetrating.

What do i do??? If i rip off the mould.....that means i will be ripping off part of my main cola...help please!

how did that turn brown like that?

i left it in a cardboard box ....would be bugs or humidity but what should i do??

flush good but dont overwater stop nutes plenty of air and pray google moldy marijuana plants

more advice people???????!!!!!!

that was good advice from tomahawk, flush really well. stop nutrients I cant see very clearly if thats mold but good procedure to stop whatevers causing it

har dto see in those pics but its odd very odd the main cola turned brown