How to make 'inactive' references 'active'?

I am not sure how to word this question. Basically, I sent a word document with endnote references to someone. They sent me back an updated form of the document (without changing around any references), however, the references aren’t ‘active’ anymore (the intext citations (e.g., [3] ) are not linked to their full citations below (e.g., John doe (2008) xxxxx) and when I add in new references from endnote, they start at [1] and a new references section is created. 

I have exported a traveling library from the original document. Is there any way to link this library with the updated document so that the references become ‘active’ and link back to endnote? Or any other way? 

Thanks for your time

Not easily.  When this happens to me – I go back to my prior version, convert to temporary unfomatted citations (NOT PLAIN) and compare it to the edited version and reject the plain text citations and accept the other changes.  It is likely they used something other than word to edit it (like google docs) which erases word fields.  (Next time, share with them the unformated {author, year #rec} (or even better i use the accession field in my temp citations) and give them a bibliography with it. )