SMS is not sent immediately

Background
Minicards and SL80xx modems are customized to attempt to send SMS multiple times. In case when SMS is not sent immediately, modem will attempt to send SMS again after predefined wait interval has elapsed. AT!SMSRETRY command defines such modem behavior.

Resolution
If you want to customize modem to try to send SMS only once, you can define such behavior with AT!SMSRETRY=0,0
Please refer to AT command guide for detailed AT!SMSRETRY description.

While testing SMS reception in Sierra Wireless AR7552 board, there is an issue with radio status. It is not getting registered to network and the signal strength is displayed as No signal strength, as below.

root@swi-mdm9x15:~# cm radio
Power: ON
Current Network Operator:
Status: Not registered and not currently searching for new operator (LE_MRC_REG_NONE)
Signal: No signal strength (0)

Note:

smsInboxService is running, so under normal circumstances, SMS reception should be fine. ** [running] smsInboxService ** .
sim information is available, as below,                


       root@swi-mdm9x15:~# cm sim info
       Type:       EXTERNAL_SLOT_1
        ICCID:      8991860000012325586
        Home Network Operator: Vodafone IN
        IMSI:       404860001232558

Please let me know how to solve this unregister issue…