I am trying to use two different arduino on two different ports. When ever i change the port number of the one node, node-red assigns the same port number to different node. This is very frustrating. I've used everything to solve but nothing worked.
you have the arduino in the same group on the node-red?
On the port. Rather than use the pencil edit button, use the drop down and add new port to one of them.
No, I'm using different arduino in different flows.
I've tried that too, but nothing worked.
Please construct a mini-flow showing the failing use of two ports and post it here so we can try to replicate the situation. See this post for how to share a flow.