Port Forwarding to Create A Minecraft Server

Issue is very similar to @kaneki512  

Here's a link to the post: https://forums.att.com/conversations/att-internet-features/port-fowarding-to-create-a-minecraft-server/6295c818f656d85d071adc89

Issue goes as follows, I try to port forward with the device running the server. Once the service is created I try to select the device with the server, but once I add the server device it changed to another device which doesn't have the server. I've tried resetting the modem with no luck. I'd appreciate any help