Bigbluebutton Integration invalid API-URL

Hi Guys,
I get the error message: “Invalid API-URL” when I try to save the API URL or API Secret. Could it be due to the use of a proxy server?
If YES how can I handle it. Proxy is entered in NC Config and bbb works fine with other frontends
NC: 18.0.6
bbb: 1.1.1

My values: API-URL: https://<
API-secret: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

One post for one issue is enough :wink:

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