"Hello, 'please call me...' Trope."
"Please, call me Tropey."
A stock phase in which a character is adressed by his/her full name, but then is told the exact words 'please, call me...' before inserting his/her prefered nickname.
A sister trope of Don't Call Me Sir
(For when a character simply objects to being called sir) and Do Not Call Me Paul
(Which is when a character hates his/her name and will be vicious in correcting someone or simply ignore them).