You cannot use your flight credit. In my case, I will pay more if I took the credit than booking a new flight for the same destination. You cannot change your roundtrip ticket to one way. So since I am not a frequent flyer and considering the current situation of the world, my flight credit is useless to me and probably for the rest of the people who got cancelled due to COVID-19. I want my money back!!! User's recommendation: Book directly from the Airline website so you at least have an option for refund.