Instead of providing the actual customer contact numbers Amazon NA provides their own numbers that once called request the calling party to provide certain information to be able to be put through.
These numbers come in with a standard US number and then .ext 0000. This in turn can break any shipping process that requires the use of said customer number.
The means to cut down or to fake these numbers are both impossible and illogical. So we have come up of a different solution. You can have your own contact details pre-filled instead of the customers, so that in the event the carrier does call the number to pass on some vital information you will be able to receive it and pass it on to your customer.
Enabling telephone pre-filling is really simple. Just go to Settings->Shipping.
Look at your Warehouse details and you will find the checkbox to pre-fill phones.
And thats it. Once turned on your shipments will automatically use your warehouse telephone number instead of the one provided in the orders details. But please be aware that it will do so for all orders, not just the Amazon ones, so you may need to turn this off at times,