Work permit was rejected 6 times, why?

hi sir, my name is Kamal, age 38, Indian Muslim from Malaysia. I came to Singapore for the first time looking for work and I got a job in a supermarket as a fish and chicken cutter. 6 times the recjet work permit. I want to know why it didn't pass when I asked the manager because he said something about race. The first time I applied for a work permit with a Malay guys and Malay passed but I didn't pass. The second time there were two Indians, two Chinese and me. , only I didn't pass. before the third time, my manager and I went to the mom's office to ask why it didn't pass, the answer from the mom officer was to try again to make a work permit name, I don't have a bad record in Singapore, so the third time I didn't pass and the fourth time I and another Indian Muslim, 1 Chinese, 1 Indian made a work permit, only two Indian Muslims did not pass. So the manager said it was because of the race but he tried twice to make a work permit for us also did not pass. So what is the reason for the Indian Muslim race not passing or there are other reasons and can you help me with your income for this problem.