An HTTPS binding already exists for the specified IP address and port combination. The existing binding uses a different ...

An HTTPS binding already exists for the specified IP address and port combination.  The existing binding uses a different certificate from the current request. Only one certificate can be used for each IP address and port combination. To correct the problem, either use the same certificate as the existing binding, or remove the existing SSL binding and create a new binding using the certificate of the current request.