Is this dialog correct? I've been using your blog to help construct a brief exchange for a story I'm writing in which an amnesiac (K) speaks with a friend (R) who he doesn't remember. K is still a little bit out of it, so it's alright if his dialog is off, but I wanted to know if the rest is correct, and whether it sounded natural: ........

R: "Bonjou, zanmi'm. Depi tanndat m pa wè w."
(Hello, my friend. It's been a long time since I've seen you.)
K: "Zanmi? Eske m konnen w?"
(Friend? Do I know you?)
R: "Ou te konn."
(You did once.)
K: "Oh...eskize mwen. Mwen pa sonje."
(Oh...I'm sorry. I don't remember.)

So far so good :)
On the highlighted part, it's better to write "konnen" instead of "konn".
You may have the sentence as: "Ou te konnen m - You knew me"; or "Ou te konnen m yon lè - You knew me once."
and if you really don't want to have the whole sentence and you want a phrase similar to "You did once", then you could write:  "Wi, yon lè" or "Wi, yon fwa", or simply "....yon lè".

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