I have my phone in airplane mode all the times, to save battery and only used with wifi in my home network, but i turn the airplane mode off to connect to the cellphone tower and get the time right, since I havent done it over a month the time was wrong and some programs were not conectin to the internet, so I turn the radio on my cellphone ( all cellphones are an advanced 2 way radios) to connect the cellphone to the tower and get the time and now all my internet programs work right, it fixed:
so TURN AIRPLANE MODE OFF AND I HOPE IT WORKS
"internet not trusted certificate"
and "Google play not connect"
and "mail.com app not updating"