Issue with unregisterd redirect uri

Hi, I have an LTI 1.3 external tool that I am developing/testing. When I try and launch the tool from Moodle, after the intitial request, it tries to make the redirect request back to my tool. But I keep getting the following:

error: invalid_request

error_description: Unregistered redirect_uri https://<the url of my tool>

When I setup the tool, I did add the url i redirect to to the Redirection URI's field in the Edit Preconfigured Tool page. Is there another place I have to go to set things up?