Draytek 2762 with SSL VPN enabled, LAN DNS used, iPhone X Draytek SSL App

I have setup a few LAN DNS entries pointing to some local devices (it's a home network with no DNS)

I have setup Draytek VPN using the IOS App which works fine. I also have setup VPN on my MAC which works fine.

What I'm noticing however is that the LAN DNS devices are not resolved when using the iPhone but work fine via the MAC. There's no DNS setting on the Draytek App , so I'm a bit lost.

Any thoughts appreciated .

S