Image centring

Hey guys,

I’m finding it impossible to get images to center properly on the page. It says align=”aligncenter” in the code and I’ve tried things that people have suggested elsewhere but no luck!
Can anyone help?

Here’s the website:
https://worldofpeanutbutter.wordpress.com/sainsburys-basic/

I don’t know what version of wordpress I’m using… or how to find out.. or how to upgrade or whatever??

Thanks!
Henry