combine edit mobile text carrier and number for holds notification

[Lindsay Stratton]

When adding text notifications for existing holds staff must first edit/add the carrier and then the number in a two step process. If the number is entered before the carrier, nothing is saved and there is no error/alert indicating that the required carrier is missing or that the operation has failed.

Is it possible to combine both elements in one popup box so that it is clear both elements must be present and streamline the process?

(version 2.7)