ERROR 404 Can't login as ADMIN

I received this message from Google on Saturday:
Search Console
SSL/TLS certificate does not include domain name https://www.seattleprofitness.com/

To: Webmaster of https://www.seattleprofitness.com/,

Google has detected that the current SSL/TLS certificate used on https://www.seattleprofitness.com/ does not include https://www.seattleprofitness.com/ domain name. This means that your website is not perceived as secure by some browsers. As a result, many web browsers will block users accessing your site by displaying a security warning message. This is done to protect users’ browsing behavior from being intercepted by a third party, which can happen on sites that are not secure.
Now I can’t login into my site using /admin. Please advise on how I can fix this issue.