You use the ChangeDeviceServicePlan API to assign a new service plan to a device. This tutorial shows the basic steps involved in changing a service plan, as carried out in SoapUI.
NOTE: This tutorial does not cover setting up and registering a callback listening service for CarrierService responses, which would allow you to see the results of the request.
Navigate to Carrier Service > ChangeDeviceState API and open a new request.
Use the SessionToken value from step 1 to add the correct <token> element to the <soapenv:Header> element:
Identify the device or devices that you want to change, and delete the XML elements for the parameters that you won't use.
Put the code for the new service plan in the ServicePlan element.
Run the request (click the green arrow in SoapUI).
The Response will contain a RequestId if the request was accepted. You can verify that the device was suspended either through your CarrierService callback service, or by issuing a GetDeviceProvisioningHistory request and looking for a Status of "Success" for EventType "Change Service Plan Confirmed" and the name of the new ServicePlan in the response.