https asp.net mvc website with valid certificate accessing WCF service hosted in http

Hello, 

Our asp.net MVC website is hosted over https & secured with valid certificate from CA. It's trying to access the WCF service over http, but it's throwing the issue as : 

Mixed Content: The page at 'https://localhost/...' was loaded over HTTPS, but requested an insecure script 'http://x.x.x.x.9999/signalr/hubs'. This request has been blocked; the content must be served over HTTPS.

We've used absolute URI for WCF service & client endpoint base addresses. 

Any pointers will be appreciated. 

Thanks,

Anindita