You have a typed number rather than a page number field in your continuation footer.
Go to that number in the footer.
Select it.
Delete it.
Type the word "Page" without the quotation marks.
Select that word.
Press Ctrl+F9 and then F9.
You have now inserted a page field.

You can also use the Insert > Page Number > Current location to do this, but I prefer doing it the way I described. It is cleaner and you have a better understanding of what you are doing.

Header/Footer Settings Recap