Cannot detect headers and footers

I have a document that has what should be some text and page numbers in the headers and footers. However, when I open the PDF in Adobe Acorbat Pro Version 2022.003.20263 and attempt to edit, I see the text is not recognized as a header or footer. Example of the expected footer text below.

Here is the message I get when I attempt to update:

The message is clear. But is there anyway I can get the headers and footers to be detected? Unfortunatley I cannot share the document because it contains sensitive information. Any help is much appreciated.  

I can provide a little more information. I am working on an NLP project. Currently the NLP is picking up a lot of false poisitives in headers and footers. Therefore, I need a way to discount the header and footer information. But since the text in the PDF is not being detected as a header and footer I cannot find a simple solution to eliminate this false positives. Thanks!!