If you are based in the UK and cannot travel to the destination due to travel restrictions, you are entitled to a refund - even if the flight operated. There may be a clause whereby you cannot cancel outside of a 30 day window, which is understandable, since the situation has always been fluid.
US Carriers - i.e. United, American and Delta are going to be more approachable in this regard, this also applies to 'vouchers' which were previously accepted but you may now want a refund.
If you accepted a voucher, it should have been valid for 2 years since most carriers had the foresight the pandemic was not going away in a few months. If your carrier has declined to offer you a refund where you previously accepted a voucher, here are a few tips :
- Take to social media
- Email their CEO
- Airline ADR [ Details on the CAA.CO.UK ]
- File a small court claim [ Your outlay starts at £35 - the majority of airlines are not going to court to defend a claim, you can also include the cost in your claim, but due diligence and save your initial queries before you reach this step ]
- A collection agent such as Flightright. They will buy your liability and you are done. They will take a large chunk of your claim, but you get something back and you are done. They in turn approach the carrier for their settlement and if it is not settled within X number of days, they issue court proceedings ].
- Finally, if you booked via a foreign carrier, i.e. Iberia, Alitalia, Lufthansa, file a complaint with their equivalent of the UK CAA. Consumer laws in Europe are stronger then the UK. The best approach is a compliant to the NEB [ ec.europa.eu/transport/themes/passengers/neb_en ]. For the US, the DOT.
Remember, the situation has been fluid from the outset because these are unprecedented times. What may have been a policy in June 2020 may have evolved and as policies have evolved, you should not be short changed.
One final point, separate tickets : I.e. BA London - Los Angeles, then United Los Angeles - San Francisco, unless your United flight was subject to a cancellation or schedule change [ usually greater than 120 mins ], you will not be entitled to a refund. Separate tickets = separate contracts, you are undercutting a through fare, it has other implications during the normal course of travel, but specifically related to this conversation surrounding COVID, the above applies. This will also be applicable if you purchased tickets on Easyjet to Zurich and a separate ticket on Turkish Airlines from Zurich - Istanbul. If the flight operated on Turkish Airlines and/or there are no travel restrictions between Switzerland/Turkey, regardless of your residence, you are treated as though you are based in Switzerland and travelling to Turkey.
Hope this helps.