Often times after the MyEducator CanvasConnect app has been installed with the correct key and secret (reference), you or your instructors will arrive at this pop-up window during the integration process (reference) and find that the app is not shown as an option. 
The easiest way to fix this is to manually add the url to the "URL" text area and name the page using the "Page Name" text area. 
The "Page Name" should be MyEducator CanvasConnect
The "URL" should be https://app.myeducator.com/links/canvas_connect/
Please verify that when copying the above url link, you copy only the underlined, red text. Any additional characters, such as spaces or periods, can inhibit the external tool from working properly.
If, after manually adding this information, the external tool still does not work, please verify the correct key and secret were saved for the external tool (reference).