A British mother-of-three who overslept and missed her flight to Spain has described being left “in tears” after discovering her family’s entire holiday package had been cancelled.

Karen Cassidy, 36, and her husband, George Gale, were due to jet-off an an all-inclusive family holiday to Malaga shortly after 7am on August 14.

But after a difficult night with their baby, the couple failed to wake up to the 4am alarm they had scheduled.

“The baby had kept me up so I don’t think I ended up going to sleep until 2am then we were supposed to get up at 4am but just slept through our alarms,” Ms Cassidy said, according to Mirror.

Rather than abandon their trip, Ms Cassidy decided to search for another flight and booked tickets to Malaga for later that day.

Their replacement flight was scheduled for about 4pm that same day, but a delay of more than an hour meant the family didn’t reach their accommodation in the southern Spanish city until midnight.

It was then that an “exhausted” Ms Cassidy realised their package deal has been cancelled.

“Obviously they were like ‘we can’t find your booking.’ Then they explained ‘actually there is a booking but it’s a past booking.’ Jet2 had cancelled our entire holiday at 3pm,” she said.

“After everything I felt we had gone through, I was just shocked.”

Ms Cassidy said she contacted Jet2 and spent about 20 minutes crying on the phone before being told there was nothing the travel company could do.

“They (Jet2) came back to me and said there’s absolutely nothing they can do, they have a no-show policy, because it’s been cancelled, they can’t go back on that,” she said.

The late-night arrival left the family with few choices, according to Ms Cassidy, who said they had to pay €350 (A$566) to secure accommodation for the night.

”At this time, midnight, we don’t have that luxury option of going to shop around,” she said.

The couple ultimately spent more than £1500 (A$284) on replacement travel and accommodation, on top of the £1114 (A$2105) they had already paid for the original holiday.

Ms Cassidy said this brought the overall cost of their trip to more than £2600 ($A4913).

Jet2 said the couple’s accommodation arrangements were cancelled because they did not board their booked outbound flight and failed to inform the company that they intended to travel to Malaga independently.

“Unfortunately, as the customers did not travel on their booked outbound flight or let us know that they planned to make their own way to Malaga, their remaining holiday arrangements were cancelled in line with the terms and conditions of their booking,” the airline and package holiday provider said in a statement, cited by the outlet.

“When they got in touch with us after arriving in resort, our team offered to try to help and support them.”

Ms Cassidy later took to TikTok, Mirror reports, to recount what happened and said she hoped sharing the experience would prevent other holidaymakers who were unaware of Jet2’s “unclear” policy from making the same mistake.

“Through loads of rubbish comments from people calling me an idiot or people saying ‘what grown up can miss a flight’, there’s hundreds of people that don’t know,” she said.

“If I could save one person, I’m happy.”