Why is "No sim card" error on my phone after I installed the navigation bar.

[AC Question]

I own a new phone "Hotwav cosmos v8" Android 5.1 lollipop mobile and it came without the notification bar. I downloaded King root and rooted the phone and it was OK. Then I used the ES file Explorer to edit my build.pro and I restored the navigation bar. Two days later, I Uninstalled the ES file Explorer and my phone started showing "No sim" I tried all the possible ways from filling up a card to the sim to entering the code *#*#4636#*#* but nothing is working. Am stock please........... Help out