Sync issues with Android and ATT.Net account

Question

In July,  I had the issue where I stopped receiving ATT.NET emails on my Samsung S4.  Found the solution by changing the incoming server setting to SSL (accept all certificates).  However, since that time my droid does seem to sync with my account - I delete emails after reading them on my droid, but they do not delete from my ATT.Net account as those emails are in my account as unread when I login to ATT.NET on my computer.  My settings on my droid are set to delete from inbox.  How do I fix this?  I am ready to give up on this ATT.NET account.

ATTHelp · Answer

Hi @OMANN621,I am sorry you are having trouble with your email. I am pleased to check into this for you!Are you using the AT&T Mail app, or the Yahoomail app on your phone? If not, the first thing I will suggest is to please try one or both of those apps and see if this fixes the issue. You can find both in the app store. Let me know if you have any questions!Geovanni, AT&T Community Specialist

OMANN621 · Answer

I use the email app that was preloaded on my phone. Up until 7/25/17 this app worked fine. On that date i stopped receiving emails on my phone. To fix the issue i had to change my incoming server to "trust all". Since this change my phone and my account do not sync. In addition i am now receiving spam emails on my phone.
I do not see an ATT mail app in the google playstore and i am no going to load the Yahoo app as they show too many ads. Why did Att change the server certs. In July and why arenty phone and email syncing?