Hyperlinks in Matala

Hello, I have a www.ads-software.com hosted by Dreamhost, if that matters. I am trying to insert a hyperlink into a post. Either the words do not stay highlighted or they highlight purple, not blue and do not work. I have deactivated every plugin already as I read those can cause problems. What am I doing wrong?

I hightlight the words I want to link in my post, go the hyperlink icon, click, add link, insert and update my page.

Thank you!