Links not working from emailed posts

Anyone have a clue as to why when looking at a post which was emailed (as past of a blog subscription), if you click in a link that href is set to an external site, the link diesnt wirk properly? Example:

http://www.abc.com emails post to subscribers. Site has visit their page “here” link which “here” href’s http://www.123.com. When you read the email and click “here” you are lead back to a page not found on abc.com (not 123.com). When looking at the address,it actually tried connecting to https://abc.com/2018/06/05/new-post-name/%20http:/www.123.com

If you look above, it doesn’t just go to the external site for some reason. When looking at the post from the actual website, links out fine. Only when clicking from email dies the issue arise. Any ideas?