IndiGo, India's largest airline, experienced fresh online booking difficulties on Friday, marking the second disruption to hit its core reservation platform this week.

The repeated technical faults represent an early challenge for CEO Willie Walsh, who assumed leadership on August 3. He took charge under five months after predecessor Pieter Elbers resigned following severe scrutiny over a major operational collapse at the carrier.

An advisory posted on IndiGo's website on Friday matched the statement issued on Wednesday, citing "intermittent issues" with the main booking platform.

It was not immediately clear whether the problems were linked to Wednesday's disruption or whether the earlier issue had been fully resolved, and IndiGo did not respond to an email seeking more details. The airline held a 67% share of India's domestic aviation market in July.

Reuters journalists in four cities were unable to book tickets through the website, which displayed a "no data available" message when they searched for flights, while some were also unable to log in to the app.

Multiple users complained on IndiGo's X handle on Friday about failed bookings, problems completing web check-ins and payment confirmations.

IndiGo came under scrutiny last December after pilot rostering problems forced it to cancel thousands of flights, leaving tens of thousands of passengers stranded and disrupting travel across the country.

The airline, which controls roughly 65 per cent of the domestic aviation market, cancelled 4,500 flights in December in what was the biggest crisis in its 20-year history, with the delays affecting more than a million passengers.

According to India’s aviation regulator DGCA, some 980,000 people were hit by flight cancellations and 640,000 were stranded at airports due to delays stretching beyond two hours.

The disruption continued for days and pushed fares unusually high on several routes.