I too faced the same issue. This error is coming because you've not chosen a service provider. No service provider is available in the location that you provided in the earlier screen.
What I did to correct it was to choose a location (city, state) in the US in the previous screen.
If you do so, "select service provider" screen wont be blank. It will show available service providers in that area. Then you need to choose a service provider by clicking a button provided at the last column of any one of service provider.
I have attached the list of service providers used in this case, you may choose any of the city and state provided in the list.