Posting An Event

I've posted one event before with out any difficulty. This time as before I added the word, 'none' in the last box for Registration Fee. When I submitted the red notice appeared above in the left corner saying I should add, 'XX,XXX.X' to the box. I keep getting this box. I have even did the 'copy and paste' thing and it still rejects my submission.

I want to submit this event as soon as possible. can someone help me.