Lan and PPTP question

I have Freepbx, dvg-7111 and dvg2102s.
So when i connect my dvg2102s as lan client all ok i can talk and can hear people.
But when i connect dvg2102s as pptp client people can hear me, but i don’t hear nothing.

Add IP network to SIP Settings/Localnet

without result

You must have done it wrong