Tech Mahindra — not getting shift allowance for about an year now

Address: TECH MAHINDRA ELECTRONIC CITY BENGALURU

Currently in tech mahindra from sept-2018,
Got a project where in they held my project allocation for 4 months or so in name of training (Was working for the project but still was considered to be on buisness wait).
Later was mapped into the project and am asked to work in 2nd (15:00-00:00) shift by my manager but he isn't approving my allowance for about 6 months now, reason being my team doesn't get enough billing...

Can anyone suggest how to act forward without risking my job...