How do I get my Missed message app working for text messages?

[AC Question]

Missed message flasher not working as expected

Hi, I have a Moto G phone and do not like that if I miss a message or call, there is no audible sound. I installed Missed Message Flasher app and like how it works for a missed call, but can't seem to get it to activate for a missed text message. In the settings section of Missed Message Flasher I have checked the "SMS & MMS" in the Monitor section and assigned a Sound for the notification. But when I receive a new TextPlus message, the phone only provides the initial notification sound and then nothing else afterwards. It works great for a missed call but how can I get it to work for incoming text messages on TextPlus? Thanks, Liz