My HTC Desire 816 dual sim phone has an error message- "Sim 2- No Service"?

[AC Question]

Hi - My HTC Desire 816 dual sim phone has this error message constantly saying -" Sim 2- No Service (Selected Network not available)" even though I have never used Sim 2. I tried switching the sim from sim 1 to sim 2 to see if the message goes away - it didnt though the phone service and 3g are working fine! I did not change any settings.. can someone help with how to get rid of this message? I recently upgraded the software to Android 5.0.2

Thanks in advance!

 

[B. Diddy]

Welcome to Android Central! In Settings>Wireless & Networks​, is there a menu for Dual SIM Settings? Is there anything there you can adjust?