Thank you for reaching out.
In order to initiate the process for becoming service provider for Azure Express Route Service, you need to create a Support request with us first with Serive Type ExpressRoute Service Provider
and fill out other fields as shown below. The support team then can take this request further with the express route team.
If you do not have a support plan, please let me know I can help in that regard.
As a Azure subscription is required to create a support request. If you do not have an Azure Subscription you can follow this documentation to create an account.
Hope this helps! Please let me know if you have any questions. Thank you!
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