I have a saver J booking ,booked online, for PER to LHR for July 22. Using manage my booking I can find an available date in August 22 and can complete the change up to the very last bit where I accept the conditions, then I get the error "cannot process your request right now. Get in touch with the local office." The phone wait is over 1 hour and the online request won't accept a departure date after 31/12/21. Anyone have any ideas?