Hello @
I assume you first try an individual enrollment.
How do you get that device-related 'CONNECTION_STRING'?
It should be returned by the DPS client after provisioning the device registration.
That device connection string returns the linked IoT Hub, the device ID, and the connection string.
Here is an example written in C#.
Here is an example written in Python. See also this blog post.
Notice the DPS will register the device in the selected IoT Hub.
First, check if the DPS enrollment is successful (it shows the state).
Then, check if the device is registered in the IoT Hub.
Please, take some time to learn about the provisioning process using this learning module.
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