Old and new contact's adresses on composed mail

My contact changed his address. I deleted the original and added the new one. Only the new one appears on my contacts list but both are offered when I compose mail. I use the new one but trying to send get the message “The message doesn’t have any valid recipients.”

What’s happening and how do I correct it?

This should handle your problem… clear the history

Thanks, but as a very inexpert user I can’t find how to access settings . . . . .

Click MENU (top left corner) and then click SETTINGS