someone DOES have the same hotmail email address as me, this is a security issue

hi, someone definitely has the same Hotmail email address as me. I have had this address for years. then a few months ago I started receiving information from ebay that was meant for this person. I contacted ebay and they asked this person to change her email which she must of done because I do not receive mail from ebay that's is not intended for me now.  yesterday I received a email from a energy company with this persons name and and energy account  number. I am worried she may be receiving my emails and this may be a security issue? what should I do please.?