A few days ago a Dub-Doh-Kul booking with QR had the second leg changed to one with MH.
I couldn't select the new seat on the QR site but could on the MH one.
A friend, on the same flights (but different booking reference) confirmed the change like me but when he tried the same process tonight to allocate a seat the MH site won't recognise the booking.
I checked the Finnair site which will and the BA site which won't.
Does this necessitate phoning MH or can he allocate himself the replacement seat on other oneworld airline sites?

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