Getting rejected multiple times after applying for credit card.

I'm working and salaried, and I have my salary account in Axis. So they call me daily like 3-4 times saying that I am selected for their free Axis Neo card and apply on their app. But when I apply for the card it's showing you cannot be offered a card. Why is this happening? I haven't taken a loan nor do I have had credit cards before. Is it because my credit score is low? But how will it be low? What should I do now to get a card?