Problem with SSL VPN(remote access)

Hello
I did exactly what is written here: community.sophos.com/.../122769
and this is the @IPs that i give to me (vpn setting)/WAN/LAN
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SSL VPN Settings (client range)
10.81.234.5-10.81.234.55 /24

@IP of WAN Interface :10.66.13.37/24
@IP of LAN Interface : 172.16.16.16

Lan Network : 172.16.16.0/24
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i downlaod the vpn configuration and i can connect with it, i can get an @ip from the range (10.81.234.5-10.81.234.55 /24)
But there is no ping, no access ressources to my local subnet, ex: i can not ping on 172.16.16.10

 How i can get access to my LAN ressources having 172.16.16.0/24