Any advice would be appreciated.

Booked via Amex for LHR to PVG return for April 25

Amex have been advised by Virgin to rebook onto BA flights, but their ticketing system keeps throwing out errors. Amex went back to Virgin and they advised the same thing and has been going around in circles for the last 2 weeks.

I tried calling Virgin but they wouldn't speak to me as ticket was via Amex

Any idea how I can escalate this with Virgin to get it sorted

Thanks

Sat