i have to choose network type after connect to vpn every time

i have to select network type every time when connecting to vpn.
at last i had to ignore this message and it never been shown again to change it in public places when it required.

Well if the VPN is assigned a different IP address with a different subnet mask then yes you will get a notification to treat the new detected network as. You can use Network Zones settings to automatically treat each new connection as either, home, work, or public.