The following Customer ID error shows when you try to create or update a list on myLists using a Digikey account that doesn't have a customer number.
To verify that DigiKey has assigned you a customer ID, log onto https://www.digikey.com. After logging in, select MyDigiKey by your name.
On your DigiKey profile page, look for the customer number under your email address as shown in the example figure below. It may take several days for Digikey to add your customer number. Contact Digikey directly with questions on your customer number.
If you see a customer number on your profile page, follow instructions in the Customer ID error popup (above) to clear any stale links. Make sure that you both log out from the Digikey website and clear account link before retrying myLists usage.