“Non-www” and “www”

Hello there,

One of my articles is ranking on the first page of Google, you can see the link here: https://masteryblogging.com/best-appsumo-deals/ [URL is non-www]

But, I have updated that articles and I aldo added www in my domain so the new URL becomes like this, https://www.masteryblogging.com/best-appsumo-deals/

But if you open both URL, my non-www article is non updated but the URL with wwww is showing me an updated article and on the SERPs reults it is showing me non updated and unfortunately it is affecting my site.

What should I do now?
Waiting gor your response

Best Regards
Sanu