How to fix "domain.com HAS SELF-SIGNED SSL. Your SSL will expire in 3649 days"?

I installed an SSL certificate on my particular website, and it’s activated there, even I rewritten the URL as well but when I try to reach my website URL through a web browser, it seems that it doesn’t encrypt ssl certificate on my website so I deleted cache and cookies and clear browser but again still I am facing the same problems that site is not SSL encrypted when I goto file manager of that particular website it shows something like ‘domain.com HAS SELF-SIGNED SSL. Your SSL will expire in 3649 days’, i am sure there it could be 365 days expire days but it shows me wrong. i don’t know to fix it so can anyone help me out to fix it?