Kumite in VF4

I just started playing VF4 Kumite mode again, and for some reason it won't give me a ranking match to move up from First Dan. Would someone please explain to me the ins and outs of Kumite Mode? Thanks in advance.

 

Kumite ranking

 

I had the exact same problem. I won 14 matches in a row but still didn't get a ranking match to move up to 2nd dan. And now i find out i gotta beat at least 50 people to get out of the dan rankings? Oi.