VPN network between Zyxel and OpenWrt?

Question

VPN

My strength is no more.
I've been fighting for a week now.
There is a network,
NET1 (ZYXEL KEENETIC GIGA II)
Local network 192.168.252
Internet - 81.123.123.123 VPN server is up, client
address is assigned - 172.16.2.10
NET2 (OPENWRT) Local
network 192.168.1.0 NET1 and NET2 installed. Routes are registered: NET1 - 192.168.1.0 mask 255.255.255.0 gw 172.16.2.10 but for some reason it is not active NET2 - 192.168.252.0 mask 255.255.255.0 gw 172.16.2.10 NET2 fully sees NET1. Pings, resources and so on. NET1 sees only 172.16.2.10, everything behind it does not see.


On the Zyxel Keenetic Giga II, I forward the port to 172.16.2.10 from the outside so that the router is accessible from the outside, but there is no access.
Access is only from NET1, that is, from the inside.

How to make everything work normally? so that NET1 fully sees NET2?