FlixBus complaint: Where was my bus Booking Ref 3136517568

I booked a Flixbus Ref: 3136517568 from Nottingham to Leeds leaving Nottingham Greyfriar Gate
stop C11 – C12 at 1:15 pm on February 5th to arrive in Leeds Kirkgate at 2:50pm seat 3a
I arrived at the stop at just before 1and queued with a lot of others a bus arrived and the driver got off disappeared and came back just after 1:45 and put 004 London on the bus??
After all the passengers who like me had stood freezing waiting for this bus had got on I asked the driver where my bus was showing him my ticket He was very helpful and called you and was told I needed to ring you to sort it. I am 72 in April and needed to get home to Leeds and had to resort to catching a National Express bus costing me £19.90 and it did not get back to Leeds till just after 5pm and it was dark and at my age I do not like to be out after dark as I feel vulnerable and scared walking about after dark