Forget about request by snail mail? (5,3)
I believe the answer is:
write off
I believe this is a double definition.
'forget about' is the first definition.
(to write off is to forget about or dismiss)
'request by snail mail?' is the second definition.
(as in writing off for something in the mail)
(Other definitions for write off that I've seen before include "Consign to scrap heap" , "Adjustment made by bookkeeper" , "trash" , "Consider valueless" , "Dismiss as worthless" .)