Someone started trying to use my nicknamed gmail account thinking they were forwarding letters to a parent/partner with I'm assuming a similar initial/name as the surname matches. Started off with harmless emails, the odd note or forwarded letter and nothing which could identify them. Today they sent a full letter with identifiable information, full address, DOB, names, the lot. I'm not sure if I should reply that they should be more careful or ignore and delete like I did with the rest. Should I leave a CD on their doorstep?