Air India - gmail com

I booked the tickets under the 'Economy Comfort Plus' because I wanted the flexibility to change or cancel my flight. I assumed the option to do so would be available on the Air India booking portal like other Airlines have. But in the manage you booking section there's no option for me to modify/cancel my flight. It's saying that my flight is not eligible for online modifications and I need to contact the customer support. But no one is picking up the phone. I want Air India to enable cancellation of the ticket and not charge me the penalty as I have been trying to cancel it within the stipulated time frame mentioned in the ticket.