Even if it is a debt collector. Even if you did owe that money, they are not allowed to do that.

Take it to the cops. File a report. It will help you and any other person in the same situation.

Sending me messages about apparantly owing them $4000. Threats of physical harm and death, funny at first but now downright annoying as they seem to have up to 50% of their information correct. If anyone could find out who it is would be muchly appreciated