Millions of people are out of pocket on flights they were unable to board due to coronavirus restrictions, according to consumer group Which?.
Travellers prevented from flying by travel restrictions or lockdowns may not be entitled to a refund.
More than 2.3 million people have not got their money back, Which? said.
Travel restrictions remain in place in the UK, with travellers arriving from “high-risk” countries having to stay in quarantine hotels.
Most of the people who were unable to take flights were hit by circumstances which meant they reasonably, or in some cases, legally, could not travel to their destination, Which? said.
It is warning people to be wary of booking flights for this summer and to wait until the situation around international travel becomes clearer.
The consumer group said in the longer-term booking a package holiday rather than a flight-only booking should give stronger passenger protections. People should only book with a trusted provider with a generous and flexible booking policy, it said.
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