Embedded YT-Videos not found after publishing course?

Hi all,

I created a Rise360 course with pages that contain YT-Videos that are embedded in an "Accordion" - Element. These Videos are displayed correctly in the preview, but after publishing the course in "Web" - format, an error message is displayed, stating that the videos can not be found?

As the deadline for publishing the course is quite close help is really appreciated,

Kind regards,

Frank

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This is one error message I got:
"The web page at file://cdn.embedly.com/widgets/media.html?src=https%3A%2F%2Fwww.youtube.com%2Fembed%2FB5u4ir33VLI%3Flist%3DPLiq3tC5R7RRpMl4yB15lACY8Km5tOHrC1&display_name=YouTube&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DB5u4ir33VLI&image=https%3A%2F%2Fi.ytimg.com%2Fvi%2FB5u4ir33VLI%2Fhqdefault.jpg&key=40cb30655a7f4a46adaaf18efb05db21&type=text%2Fhtml&schema=youtube might be temporarily down or it may have moved permanently to a new web address."

Screenshot form rise360 editor:

Screenshot in preview:

Screenshot error message in published web course: