I can´t delete my Powerpoint Pages

Well my friend, unfortunately there's nothing we can do to help you. You'll need to contact Microsoft Official support for business to see if they can delete the old tenant for you.

I repeat again, my point is that I want to make a screencast video using PowerPoint. In this video you can see the interface of PowerPoint. I want to re-license this video with an open license. So I want to allow others to copy, modify, distribute, display, license or sell the video.
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<br />Can you specifically answer this question for me?
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Thanks a lot for the reply! If you dont mind, I would like to elobarate my question in english. First problem is that I would like to add a word document (coverpage) to my word document. This coverpage is already prepared. But I have to merge this two word documents. How is it possible? The second problem is when I add a header in the coverpage, it appears in the other pages also. How can I fix the header just in the first page? Third problem is that I have deleted some references in the bibliography, when I update the bibliography, the deleted references don't disappear. How can I fix it?
<br />Kind regards
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Hello Diane,
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<br />thanks for your fast response and apologies for replying so late. Meanwhile I did some testing on that issue.
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<br />I can delete another standard group (e.g. "New") in the ribbon. This seems to be permanent. It does not come back automatically. As far as testet, the Group "Language" is the only one with this special behavior: I can delete the group but after some time it's back again. So there is something working in the background which overwrites my adaption. But what and where to change?
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where i can find my admin contact data