How do I contact support to find the last known location of my iPhone?

Hi,

I have lost my cellphone. I need to email support because I do not have a phone to call them with. I cannot seem to find their email address.

My problem is that I lost my cellphone and I was unable to find it with Findmyiphone app. I know it was online because it was not off when i lost it. Now it is off and I am wondering if they could tell me what its last location was. I have been looking for it everywhere. This is the second time that the Findmyiphone app has not worked. Do I need to be right next to my device for it to work? thanks for any help.