thank you for your suggestions...
it is a simple notification extension and currently only runs on older Android versions, i.e. < Android 8
therefore my recommendation for you is to use one of the other available notification extensions
I wil add a note on my webpage. thank you
Notification Extension by Juan Antonio
Notification to Status Bar Extension by Tiziano1960
New Improved Notification Extension by Tiziano1960
MediaStyle Notification Extension by Ken (15 USD)
Notification Badge Extension by Preet_Vadaliya
Notification Stype Extension by jarlissonlira2 with various types of notifications
Push Notification Extension by jarlissonlira2 to receive notification through onesignal
taken from the extensions directory https://puravidaapps.com/extensions.php
Taifun
Trying to push the limits! Snippets, Tutorials and Extensions from Pura Vida Apps by 
Taifun.