British Airways has been forced to apologise over a "glitch" that bars women from using the title doctor when booking flights online.
The flag carrier said it was "urgently investigating" issues with its website following a customer complaint.
An American traveller, Juliana Kling, posted a picture of BA’s website on Twitter along with the comment: “Apparently ‘Dr’ and ‘woman’ do not match on British Airways. Looking forward to their reply.”
A BA spokesman said: "We’re sorry for a technical issue that has occurred in one drop down box on our website and we're urgently investigating."
A picture with Ms Kling’s tweet showed an error message on the BA website saying “Title and gender do not match. Please try again” above Dr Kling’s attempt to input her details as a female doctor.
The comment prompted hundreds of infuriated replies on social media.
British Airways has been beset by IT problems in the past, including a number of IT failures that have caused flights to be delayed and cancelled.
In March the company apologised for an hour-long IT glitch that triggered a wave of cancellations at Heathrow’s Terminal 5.
Earlier this month a Telegraph reader took BA to court and won after it cancelled his flight but refused to refund him to his satisfaction.
The airline also suffered a months-long hack of its payment systems in 2018 resulting in a £20m fine from data protection regulators after it came to light.
BA staff are preparing to strike in July, with baggage handlers and ground crew walking out over demands for a 10pc pay rise.