mobile web browser reads "Not Secure"
I am having trouble with my mobile webpage I set up with Duda. When I click on my page, the page opens but in the browser window it reads Not Secure. What is wrong? How do I correct it? I do have the CNAME recorded with my provider Network Solutions and I have a SSL Certificate with Network Solutions. Do I need another Certificate with Duda now? Please help. Thank you.
Here is the text from the browser window:
Here is the message: