how to make service reference for webservice that requires client cert

im trying to call a webservice that requires a client certificate

so i open VS2015 and try to add service reference

i came up with the following error

 

There was an error downloading 'HTTPS URL/$metadata'.
The request was aborted: Could not create SSL/TLS secure channel.
Metadata contains a reference that cannot be resolved: 'HTTPS URL/'.
Could not establish secure channel for SSL/TLS with authority 'HTTPS URL'.
The request was aborted: Could not create SSL/TLS secure channel.
If the service is defined in the current solution, try building the solution and adding the service reference again.

 

so i have google it ,and i came up with alot of things to do 

the first thing i have done is add the pfx file to mmc at personal part

also add the cert to the Trusted Root certificate authorities

 

also tried the following command

CertUtil -p PASSWORD -ImportPFX d:\pi-client.pfx

Certificate "WesternUnionPartnerIntegration" already in store.

CertUtil: -importPFX command completed successfully.

 

then i tried to add the service reference again but still the same error !

 

i dont know where is the issue , i have worked with alot of webservice with https but with no client certificate 

i need help !!

Thanks