MCent — I didn't earn reffering friend's talktime

I didnt get my refferal talktime through my link friend's installing and app download. Friend's get app money. But i didnt get refferal talktime. Please help me. . Rply. . If help me. . I will give u more mcent users. I invited lots of friends and all of installed mcent aplication. But i didnt got refferal talktime. My number [protected]. Am waiting ut rply. . And i need more friends to sign up also. .