Hi there
I know your post is a bit old so I don't know if you've find an answer.
I'm not sure I understand what you mean: Is you dad in France and sign up for a letter for you in france?
If that's the case I assume he knows the postman cause unless you've left him a "procuration" with a valid ID of you, he won't be able to retreive the letter.
If not if you only got the receipt of the letter you should have a number on it and with that the post office should be able to track down the sender.
I know your post is a bit old so I don't know if you've find an answer.
I'm not sure I understand what you mean: Is you dad in France and sign up for a letter for you in france?
If that's the case I assume he knows the postman cause unless you've left him a "procuration" with a valid ID of you, he won't be able to retreive the letter.
If not if you only got the receipt of the letter you should have a number on it and with that the post office should be able to track down the sender.