Phone Answers When Touched- How To Stop?

Hello All!
I have a ZTE Maven using Android 5.1 Lollipop and AT&T Go Phone.
When the phone rings and I touch it to take it out of my pocket, the call is answered.
This is a new behavior. I used to have to swipe down on the screen to answer.

I have searched every setting & sub-setting on the phone with no luck.
Internet searching has many articles, some specific to Lollipop, but my phone does not have the buttons to press as shown in the articles.

Do any of you know how to turn off answering unless I swipe down?
Thanks Very Much for your help!
Paul

 

Thanks Danny for answering. I appreciate your help.

I haven't put any new contacts for months. (Boring guy that I am)
The dialer app is the one that came with the phone. I tried to find a version number in case it helps, but couldn't find any info on it.

I almost certainly am touching the screen or a side button when taking it out of my pocket.

What puzzles me is that I've always taken it out of my pocket the same way and always had to swipe down to answer- sometimes several times if I swipe incorrectly.
Now it seems touching the screen or a button answers.

 

Thanks Danny Det for taking time to help & offer good suggestions.
I looked around the Play Store & saw lots of promising looking dialers. I'll experiment around with some.

I'm chicken to do the stock ROM thing, but if all else fails...

Thanks Again & Enjoy Today!
Paul