Hello,
We run into a strange problem when using a custom connector to a REST API, and we hope anybody here can help us!
A call to the API should return a JSON object, and when we test the custom connector it works fine. The schema is validated correctly, status 200 is returned and the response body contains the object we want.

When we use the connector in a canvas app however, we get the message "The data returned into the response is invalid. Response data should be a valid JSON object."
In the Power Apps Monitor we see that the response body is empty when run it from the app:
"response": {
"duration": 170.35,
"size": 0,
"status": 200,
"headers": {
"Content-Length": 0,
"Date": "Mon, 25 Jan 2021 11:54:11 GMT",
"x-ms-apihub-cached-response": true
},
"body": ""
}
The connection is OK, but the body should not be empty. When run from the Power Apps test environment or from Postman, the desired object is returned without any problems.
The Swagger file from which we constructed the connector is attached to this message.
Would anybody know what we are doing wrong here? Any help is very much appreciated!