Delay in re-connecting to network after lost internet connection

I am using hamachi on Ubuntu 16.04. My internet connection is unstable due to which internet connection is lost sometimes for a short period (say 10-30 secs). But once the internet connection is re-established the VPN connection is not reachable.  If I try to ping other nodes on the vpn network its not reachable. It is the same for some 10 - 15 mins and then the vpn connection is again re-established and I am able to ping other nodes. But every I lost internet connection the vpn network is not accessible for 10-15 mins.