There was a news last month about banks slowing down issuing new credit cards. It mentioned credit cards default rate was very high.
Banks are proactive, they continue to assess risks and take control of the things that are eating into their profits - in this case high credit exposure to credit unworthy users.
I have seen unemployed students/people getting lakhs of credit limit through Apay card. Also seen people getting huge credit limit enhancement like 20k to 2/3L 30k to 4L!
OP - You are just unlucky to get caught in their algorithm. As someone suggested, ask for LE with salary slips.