Before enquiring about the whereabouts of your order please note the impact of the recent Royal Mail strikes.
Orders posted as long ago as Monday 21st November have possibly still not been delivered.
Add that to the strike days of 23rd & 24th, 30th November and 1st December, and Royal Mail is massively behind.
They don't appear to be scanning everything either, so take that into account when tracking your order.
Further strikes are planned on 9, 11, 14, 15, 23 and 24 December.