lost link between citations and references

Hello, several authors reviewed my document and it came back with some changes in the endnote format. Although I can see all citation numbers are in gray they don´t seem to be linked to the reference (which does not shade in gray). In fact, after adding a new reference, endnote assigned a new numeration starting from 1 again, ignoring the previus one.

Is there a way I can rescue old citation-reference link so don´t I have to start all over again?

Thank you very much!