just optimized text to fit on pages, but with page numbers footer text does’t fit anymore…
Work on menu Format > Page… Margins … Header/Footer
Write more details for more detailled replies… 
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[iro on]Okay, you passed lots of details to me, thanks a lot.[iro off]
I uploaded a sample for you. Please check again: menu Format > Page… Margins … Header/Footer - and yes: if a frame is anchored in header or footer it shows up in each other page if it is based on the same page style. Please have a look to page style on status bar.
There are some other options to reduce text space on a page: character (size and/or scaling); paragraph (line spacing)
If you would like to alter the later given hints, so you could install the helpful extension paraDTP (it was made for OpenOffice 3.x but still works on LibreOffice 6.0.x).
My text is optimized to fill as much as possible of the page. When i add the footer (which i need when i want page numbers?) Two lines move over to the next page… that is the problem. I want page numbers without having to delete text 
presumably you already have a header which includes a title, date & perhaps time. if room permits you can add “page nn of nn”