I just rebuilt the netmaker sever. VPN was running normally by default creation.
however, after I modified ipv4 ip address ranges. it stopped working.
so, I deleted the vpn network. created a new VPN network. same things.
check the error logs.
Here is what it said
error running command: wg-quick up /etc/netclient/config/nm-vpn.conf
/usr/bin/wg-quick: command substitution: line 295: syntax error near unexpected token `;'