VISA FOR MY FMAILY

SIR , AIM WORKING IN CHINA GUANGZHOU FROM LAST 6 YEARS , AND HAVE AREGISTERED COMPANY , AND A Z VISA, AND IAM TRYING TO APPLY THE DEPENDANT VISA FOR MY WIFE AND KID, BUT EVERY TIME THEY REJECT THE MARRIAGE CERTIFICATE . AND THEY NO TELL WHY THEY HAVE REJECTED THIS . SO CAN U PLZ TELL ME WHAT PROCEDURE I SHOULD ACCEPT SO THAT MY FAMILY CAN GET THE VISA