DHL tracking number like many digits

Format of valid DHL tracking number (for premium shipping)

Hello everybody,

I'll soon be crazy and therefore ask for your help / information: How do you enter DHL tracking numbers (in which format) ??? I am a DHL business customer and receive 20-digit tracking numbers for DHL parcels within Germany. I thought I would give this to the order confirmation ... Problem:

I registered and qualified for 2-day premium shipping a few weeks ago. A short time later my authorization was withdrawn due to “invalid shipment numbers”. As I said, I send via DHL parcel and have copied the shipment number from the DHL business customer portal and added it to the order confirmation. All shipments can also be validly tracked.

So I opened a ticket on Amazon and reported the problem because my tracking numbers actually work. Answer: "A tracking number must always be entered into the system as follows so that the system recognizes it as valid:
If the tracking number only has 13 digits, a 0 must be placed in front of the first digit
If the tracking number has 15 to 17 digits, only the first 14 need to be entered
If the tracking number has up to 25 digits, only the 4th to 17th digits may be entered ”

Okay, so my DHL shipment numbers, which the DHL portal generates for me, have 20 digits. So I leave out the first and last 3 digits according to the above rule.

E.g. 20-digit DHL package number 00340434163565501297 -> results in tracking number “40434163565501”.

But the system still reports that the tracking numbers are invalid.
My new ticket is unanswered at Amazon.

Can you please tell me what the problem might be?

Many Thanks,
Karin