Can any one knows a part number of door handle (red square box in the picture) ?? I'm missing the part.

Also, is it possible that to be fixed for warranty at Infiniti service?

 

its called an escutcheon, if you call your dealer they usually have some or can order one for you. Sorry, dont know the part number (it varies with color) I believe those go for around $20, i bought one for my driver side door without the keyhole for a cleaner look.