Read description, is my iPhone hacked?

I keep getting notifications saying
"Cannot Verify Server Identity
Mail cannot verify the identity of "". Would you like to continue anyway?
Every time I click cancel. However, right after I do, the same notification pops up several times afterwards. The notification also comes up for other servers like "".

I have also been getting this notification:
Verification Failed
The certificate for this server is invalid. You might be connecting to a server that is pretending to be "" which could put your confidential information at risk.

These notifications come randomly when I'm on apps such as Instagram, Settings, and Mail.

My battery has also been running out quicker. Yesterday, it drained to 1% in around four hours, and it stayed at 1% for around thirty minutes.

Added (1). Oh, and my time changed to 6:09 on January 5, 1950. I went to "Date and Time" in Settings and undid the "Set Automatically" button and then clicked it again and all the time information went back to normal.

Virus! Or maybe a fake app that deletes the core network files
but the primary fix for now is factory reset your iphone or call tech support