If you get the error "This collection already contains an address with scheme http. There can be at most one address per scheme in this collection." , then apply the fix mentioned below.
Navigate to the folder specified in the error detail. Open te web.config file in the notepad.
Search for <system.serviceModel>, and add this on the next line:
<add prefix="http://YourWebsiteHostHeader" />
Replace YourWebsiteHostHeader with the Host header of your Site. It should be your website URL