Error when configuring Apple APNS

When I upload my .p12 file and give the corresponding pass phrase,  I keep getting the following error 

Encountered an error connecting to apple's servers with this certificate

Why is this so? 
 

This means we could not use your certificate to make an SSL connection to Apple. Your .p12 file is either invalid or isn’t a certificate for pushes. I recommend you try recreating it. You can use our provisionator to quickly recreate a .p12 push certificate.

If you’re still seeing this issue please send your .p12 file to support@gamethrive.com

Thanks.

This means we could not use your certificate to make an SSL connection to Apple. Your .p12 file is either invalid or isn’t a certificate for pushes. I recommend you try recreating it. You can use our provisionator to quickly recreate a .p12 push certificate.

If you’re still seeing this issue please send your .p12 file to support@gamethrive.com

Thanks.