Sometimes this mishearing happens because of constant firing of neurons in a person's brain about a particular name or the name which resembles the name they just hear. So, simply speaking they must have heard or have a strong connection with name they mis-spelled instead of yours. Although it's very weird thing to happen to anybody, more like frustrating but at the same time it's funny.
Well, sir you always shares your life experiences in here which is actually commendable, not everyone can share their life experiences with this much free-ness :)