Tvheadend

Hi Forum
Just have made some changes in my network - and having now this issue

My Clients are all placed in the LAN Zone 172.16.250.0/24
My Server is placed in my DMZ zone having IP 172.16.20.101

But when my Kodi connects to the PVR - it will just trying to get the Channels
I do not have any issues on my tablet ( Allso in LAN zone) but I cannot make the KODI on the raspberryPI connect to the TVheadend server

(Earlier it was all in the same subnet - but wanted to seperate my things)
In the Old setup - everything was working fine without problems.
I can from my PI - use ssh to the server - ping and also get the webadministration interface on the RaspberryPI ( Only changes I have made - was changing to the new IP )
But now its stock on reading channels from the server

But as I see - I'm connecting to the server

INFO]:htsp: 172.16.250.21 [ pbj | Kodi Media Center ]: Disconnected
2019-08-08 09:06:11.220 [   INFO]:htsp: Got connection from 172.16.250.21
2019-08-08 09:06:11.221 [   INFO]:htsp: 172.16.250.21: Welcomed client software: Kodi Media Center (HTSPv34)
2019-08-08 09:06:11.222 [   INFO]:htsp: 172.16.250.21 [ Kodi Media Center ]: Identified as user 'pbj'
2019-08-08 09:06:11.222 [   INFO]:htsp: 172.16.250.21 [ pbj | Kodi Media Center ]: Privileges updated

So where can this error be ? - I verified that I'm NOT only allowing special subnets ( allowed Address is set to 0.0.0.0/0