Old email contact keeps showing up

I recently added my gmail account along with the original email account I have been using.  Problem is that any email contacts that I have deleted still come up in the window when I type in the name. So if someone changed their addy and I type in their name I will see both the new one and the old one.  This could be a problem if I choose the wrong addy.  I tried looking around to see if the old email addresses are in some folder that I missed but can’t seem to find them.  There has to be a reason why the program is remembering the old email address but I can’t seem to find where they are hidden.  Can you help?

After searching the site a bit longer I did find the answer that was already answered a few years ago:
Tools > Settings  > Mail > Compose and click on “Show recipients”

Thank you