How to send SMS from terminal in background on Android?

I'm trying to send text message (SMS) from my Android terminal app in background (sim 1 or 2). I can send message in foreground using this command:

am start -a android.intent.action.SENDTO -d sms:121 --es sms_body "test text" --ez exit_on_sent true;
input keyevent 22;
input keyevent 66;

But this command don't work in background. So, how can I send message in background from my terminal? **Note: Android version 6.0. Rooted device**