The security report shows that the app is safe. My Viettel is designed by Viettel media Inc and its category is Tools. This application was downloaded and installed by over 10M users and the most recent stable update was on Oct 13, 2020.
The overall user rating of the app is 3.9. A free .apk installation package of My Viettel 2.6.2 can be downloaded from Droid Informer and you can check out users' reviews on this site. Prepare 21 MB of free space on your device for this app installer and keep in mind that it works fine on Android 4.0 and higher.