How to increase your credit limit

Same as above. I have an HDFC credit card for which I want the limit to be increased. The card has been in use for around 2 years, and the card is very active as well. How do I go about increasing the limit on this card? The HDFC bank app does not let me use the increase limit option.

What other options are there for me? Is there an email or a support number that I can reach out to so that someone would be able to help me?