I have a Asus Zenfone Max M1 ZB556KL. One system update notification from ASUS showing last few days. Today I want to do it. After ASUS system update my phone is having a "No Service" issue. The phone can read the sim card but it can't seem to receive any signal. I have confirmed that the sim card that I am using is working or not so I am swap with other one and tested it on another phone. I have done all the guides i could see on the internet eg. factory reset the phone, set the phone in airplane mode, changed sims, reboot the phone, boot in safe mode, but still, it still cannot receive any signal. Suddenly I am fall in a problem in this crucial time.