Hello, looking for advice really. We booked a last minute holiday and I checked in on line as soon as I booked. I paid (£18) so we could have one adult sat with one child. On the return flight there were no seats available that were next to each other so checked in without paying anything. So I've ended up with two seats together but two are separate. On line chat have said it's £13.99 to change the seats.i don't know how they suddenly have seats available next to each other. Will they move one of us or do I need to ring and pay?