The Boyz's Younghoon has issued an apology letter for causing trouble after making up a phone number as a joke with fans. 

On February 18, Younghoon stated via The Boyz's fan cafe,

"Hello The B, it's Younghoon.

I would like to once again apologize for the trouble I caused on the evening of February 16, when my messages on the private message platform inflicted damages to an unrelated individual. I've offered my apologies to the person through my agency, but I apologize here once again.

I was being careless as I felt comfortable talking openly with our fans.

I've realized that the number that I mentioned, made up using The Boyz's debut date, was actually a number in use.

I sincerely ask fans to understand and cooperate so that there will be no more damages.

I will do my best from now on so that I can be more cautious and careful while communicating, in order to only show you my good side.

Thank you."