Ask HN: GMail Username Issue

I have a user id to gmail that is [email protected]. Gmail has assigned [email protected] to someone else. All his personal (including his banking details) emails are showing up in my inbox and also, he tries to reset the password every other day and that also shows up, in all the emails that is associated with my gmail account. Gmail says joe.none & joenone are the same email addresses, but I can guarantee you this is not the case. Has anyone run into this issue? If yes, please direct me in the right direction to solve it. Thank you.