I upgraded my S7 to a X20 and now address reservation stopped working. In addition port forwarding and static routing disappeared.

When I delete the ip address reservation and add it automatically it changes the ip address to an automatically allocated one. However when I delete it an add it manually it ignores me and keeps the old address assigned. I need to have my devices with very specific ip addresses which still falls in the allowed range, so using the automatic option will not work for me.