Multiple Static ip Routing and port fowarding them all to the same ports.

Hi yall i have 13 static ips I purchased from my isp (spectrum biz) i also have a switch which is the netgear business Gs108tv3 switch , i have verified that it is a layer 3 switch that is capable of ip routing. My isp is spectrum and i am using thier provided router that has all 13 ips loaded up inside by the tech. I have my 4 devices plugged into the switch..which the switch is plugged into a single Ethernet port on the back of the router.

Now i have port fowarded all my devices to the the port lets say “1248” and have assigned each external address section in the add rule section with a different static ip. So so far i have assigned 4 different static ips to 4 of my devices and port forwarded all of them. THE PROBLEM IS ports show open when i use a port checker but my devices are not being affected accordingly. What could this be from. Any help would be greatly appreciated.