The problems began around 12.30 pm on Saturday.
IndiGo Airlines is facing a major technical glitch and there have been reports of long queues at airport check-in counters as well as difficulties booking tickets.
The problems began around 12.30 pm on Saturday and, around an hour later, the airline confirmed that it is experiencing a "temporary system slowdown" across its network. It warned that passengers may face increased wait times, including longer queues at airports.
In a post on X, the airline posted, "We are currently experiencing a temporary system slowdown across our network, affecting our website and booking system. As a result, customers may face increased wait times, including slower check-ins and longer queues at the airport."
IndiGo said its teams are available to assist people at airports and that efforts are on to restore normalcy as quickly as possible.
"We regret the inconvenience caused and appreciate your understanding and patience during this time," it added.
On social media, some users posted photos of long queues at airports and complained that they have not been able to book the airline's tickets, including on its own website.