Email notification shows wrong signor

Sometimes when I get an email notification saying someone signed... it states the wrong email address signed.  For example:

Signor 1: joe@email.com

Signor 2: kim@email.com

Signor 3: jane@email.com

Joe signs & it moves on the kim. I get an email saying joe signed.  Kim signs & I get an email stating joe signed yet when I open the document, clearly it shows kim signing.  I believe it is just an issue with the notification but why does this happen?  It has happened more than a couple times to me as I use the program all day long & send a ton of documents out.