Client pptp can't connect to pptpd server

[sarenos]

I have pptpd server ubuntu 16.04 in a machine with several interfaces and I want to connect pptp through the tun0 but it doesn't connect.

If I debug in /var/log/syslog I have this error

LCP: timeout sending Config-Requests Connection terminated. Modem hangup pppd version 2.4.7 and pptp version 1.4.0 no iptables rules, no ufw enabled.

Any ideas??