Cisco problems with vpn pptp, packet loss through each packet, what is the reason?

Question

Cisco

Good afternoon, I have a Cisco C881-K9, I opened a vpn tunnel, but there is no ppp encrypt in the settings, I don’t know if this is related, but when checking the availability of any of the resources behind the router, packets are lost, through each packet.

Answer 1

Most often, packet loss means that you have two balanced default routes.

Answer 2

what is the problem, if you check resources for cisco, if you let pings to the local address of cisco, then everything is fine.