Sounds like our experience is similar to most. Paid almost 1,000 Euros for a shipment from Sweden to the UK. So far it's delayed by two weeks because they never sent my completed customs paperwork to their customs department and didn't look into it when I contacted them twice to ask what the delay was.

20th November - DHL collected, estimated 4th December delivery
24th November - DHL request I complete customs paperwork. I return it within two hours.

25th November - DHL want the paperwork revised. I return it within one hour.

28th November - I ask DHL why it is still in customs according to tracking. They say customs hasn't cleared it and there's nothing more to do.

1st December - still no movement. I ask DHL what's happening. They say customs hasn't cleared it and there's nothing more to do.

5th December - I give up and contact Gerlach UK (the customs dept owned by DHL). They say they never received the paperwork from DHL so I send it directly to them.

8th December - DHL confirm Gerlach have approved the shipment to finally leave Sweden (two weeks sat in customs for no reason when I completed the paperwork within two hours!)

11th December - no tracking update. Asked DHL what is happening and told perhaps it will be delivered on 16th December, but no guarantees. If the delay is due to their mistake, why are they not prioritising my delivery? Presumably because every shipment they care for is also delayed. I am beyond disappointed that this mistake wasn't picked up on the two occasions when I contacted DHL to ask them to look into it. I run a small business and having a vast amount of stock stuck in a customs warehouse for weeks on end is costing me a fortune. I'm not a huge corporate entity like DHL and I can't afford for these errors to happen. They need to sort out their service and listen to their customers when they request that they look into things.