Thanks, my copy is by G.Schirmer and it has fingering of 5 and then 4 over the tied notes suggesting they are both to be played. To me this is a contradiction and the tie is unnecessary, so I assume it's just an error of the edition.
Depends in the edition you are using, Chopin often gave different versions of a piece to different editorials. So, just do it like it's written on your edition.