Reseller needs Customer ID for zero-touch enrollment

Hello everyone,

we want to register with our reseller for zero touch enrollment.

I gave them Costumer ID from our organization. 

I found it in the organization workspace account and in play.google.com

They told me thats the wrong number, but they did not know how to get the right number.

The number should be a ten-digit number?

So my question where to get or to find the right Customer ID, which a reseller need.

Thanks