If you cancel your Turkish Airlines reservation within 24 days of making it, you will receive a full refund. There's no reason to pay when you can cancel your flight tickets for free.
If you booked your flight tickets with Turkish Airlines, it was most likely because the prices were affordable. However, once you've made your reservations, read the Turkish Airlines 24-hour cancellation policy and procedure for cancelling your reservation and receiving a refund.
However, finding accurate information from a trusted source is challenging. So here's some assistance: you can either call Turkish airlines' customer service numbers and inquire how to cancel your reservation and receive a refund.
UK: +44 0844 800 66 66
Turkiye: 0850 333 0 849
Switzerland: +41 848 444 849