VIP Does not work Fortigate 5.4

hi 

i have two interface lan and wan

lan:10.1.1.1

Wan 5.5.5.5

and for access web server from internet (Destination nat)

I have create VIP 

srcINT WAN
SrcInt LAN
Src IP any
mapped ip 5.5.5.5 to 10.1.1.5

and one policy for lan to wan (access Internet)

and wan to lan (destination nat)

and policy WAN to LAN

 srcintf "wan1"
 dstintf "lan"
 srcaddr "all"
 dstaddr "VIP"
 action accept
 schedule "always"
 service all

Users have Internet

but Destination Nat Doesn't Work