Hi frnds, I am using Micromax Canvas A1 dual sim phone. I am having an internet pack on one of my two sim cards while other is used for calling only. Everything was fine till last two days. I update to Android 5.1.1 and my phone is automatically changing data sim and as a result deductions from main account balance on other sim card are being incurred. Now i have deleted APN settings for that sim so to avoid charges. Plz help me.