On our website, users can type in their phone number to verify it. We initiate the call and pop up a verification code on the screen. However the dialog box stays up indefinitely, until the user closes the box. This leads to a frustrating user experience as people don't think their number was verified, because the screen hasn't updated.
For technical and political reasons I cannot continually poll the server in the background to determine if the call succeeded or failed, and update the UI accordingly. I can poll the server only one time to check the status.
Is there another way I can indicate on the screen the success or failure of the call?