Nikah.com has an SSL certificate but this does not mean that Nikah.com is a legitimate website.
You should only perform online purchases with websites that have a SSL certificate (padlock shown in the address bar).
Domain trust report for Nikah.com:
Nikah.com was first registered 25 years 218 days ago.
Nikah.com has some age to the domain name which is a good sign.
Domain age: Few years old