Hi Linda - the issue is that you're confusing your profile pic with an avatar. An avatar is the little pic that displays in the box next to a post. To set an avatar, go to User CP at the top, then scroll down the left side of the page that opens to Settings & Options and click on Edit Avatar.
Scroll down to Custom Avatar, click the circle for Use Custom Avatar, then, if it's the same picture you have in your profile and it's on your hard drive, go to Option 2, click browse, find the pic on your computer, Open it to load it into the Option 2 box, then be sure to click on Save Changes at that bottom. That should set the pic as your avatar.
"Your vision becomes clear only when you look into your own heart. Who looks outside, dreams; who looks within, awakens."
Carl Gustav Jung (1875-1961)