Problem description
"OneNumber" is a Vodafone product and should not be part of Camara documentation.

In scenarios where a primary MSISDN is shared between multiple devices, each of which has its own "secondary" MSISDN (e.g. OneNumber), the MSISDN passed by the API consumer will be treated as the secondary MSISDN, and hence the identifier returned will be that of the relevant associated device (such as a smartwatch). In such scenarios, the "primary" device (e.g. smartphone) is usually allocated the same primary and secondary MSISDN, and hence providing the primary MSISDN will always return the identity of the primary device and not any associated devices.

Also the term "identity" must be replaced by the term "identifier".

Expected action
Remove the product information. Use "identifier".

In scenarios where a primary MSISDN is shared between multiple devices, each of which has its own "secondary" MSISDN, the MSISDN passed by the API consumer will be treated as the secondary MSISDN, and hence the identifier returned will be that of the relevant associated device (such as a smartwatch). In such scenarios, the "primary" device (e.g. smartphone) is usually allocated the same primary and secondary MSISDN, and hence providing the primary MSISDN will always return the identifier of the primary device and not any associated devices.

Actually, I think this text is too MSISDN-specific. E.g. in TS.43 ODSA there is the field companion_terminal_id which is a string preferably an IMEI or a GUID for companion devices (e.g. SmartWatch). If the companion device is associated by the telco using companion_terminal_id then that identifier could also be using as an API parameter in this API to identify the companion device.

How about this text?:

In scenarios where a secondary device, e.g. a SmartWatch, is associated to the primary device (Smartphone) by the telco, then providing the identifier of the secondary device in the API request results in returning the device identifiers of the secondary device. If the telco does did associate the secondary device to the primary device an error is returned.

Should somebody write a use case for this scenario?