as @JimPas wrote: You have only mixed content.
Your certificate is new and valid - https://check-your-website.server-daten.de/?q=indmissionasean.gov.in
CN=www.indmissionasean.gov.in
15.04.2020
14.07.2020
expires in 90 days indmissionasean.gov.in, www.indmissionasean.gov.in - 2 entries
but a lot of images with http links.
Sample:
http://www.indmissionasean.gov.in/images/footerCoursal/asean-india-center.jpg
See the Html-Part of the online check.
And one error in a stylesheet:
https://www.indmissionasean.gov.in/css/5.css
is https, but
http://fonts.googleapis.com/css?family=Open+Sans:300italic,400italic,700italic,300,400,700
included with url("...") is http.