How to get china business visa for longer stay

Hi,i'm indian citizen and i applied for china business M for 1 year ,unfortunately my visa got rejected and after resubmitting the application i got only 15 days stay ,now i have traveled and stayed in china for 15 days and now i want to apply again for business M,can anyone let me know how can i get longer stay business M??

Is there any procedure or will i get 15 or 30 days stay again i apply??

I need at least single entry 90 days or 6 months with multiple entry for 30 days in mainland.