I don't understand why people get so annoyed about being called shortened versions of their name.
There was a woman at my old work who was a "Pamela" not "Pam". You must not call me "Pam" she said. I asked why, particularly as James Corden had made Pamela a bit of a joke through Gav and Stace. She said it was because he Dad named her Pamela not Pam and refused to let her be called anything else.
She told me her friends would ring the house and he'd pick up the phone to them asking for "Pam" to which he'd reply "no one here goes by that name" and then hang up. She was very proud of this. I just asked her if she was sure that was the reason she didn't have any friends or if he made it up to make her feel better. Wiped the smile off Pammy's face straight away that one.