Answer: Last Updated: Jun 18, 2018 Views: 6
Problem Solving Method 1
[Follow the different steps on the pictures enclosed, as well]
Double-click on the header or on the footnote zone, on the first page where the number is incorrect. 
This action will activate the tab called "Header & Footer Tools" (under "Design"). 
Disable "Different First Page". 
Warning! This action can (also) totally destroy your first page's layout!!
If this doesn't seem to work (but doesn't destroy anything), keep it disabled and follow the...
Problem Solving Method 2
Right-click on the first number that is wrong to open the menu.  
Click on "Format Page Numbers..." 
Choose "Continue from previous section". 
And that should fix it!!
If there are many wrong sequences of page numbers in the document
Reproduce those 2 methods, in that precise order, for every (first) number of each sequence that is wrong in the document and it should automatically fix the whole sequence.