connecting two HMI to modicon m340

I have connected two HMI to modicon m340 via an ethernet switch and trying to program the pls using Unity Pro.How can I link these two hmi's to the plc ethernet port. In the program after dbl clicking on the ethernet port of the PLC , it just allow me to link only one touch panel

You need to have an IP for each device in the same class IP.
On the ethernet port of the M340 you write an IP in the same calss ip with HMI IP.

For communication with first HMI you must create the variables in PLC with same address that you have created in the first HMI.

For communication with second HMI you must create the variables in PLC with same address that you have created in the second HMI.

Or, of course, you could use C-more panels, and serve tags from one, to the other, without being limited at the PLC connection point.....
(just sayin')

I like c-more and ab. But my customer has asked me to use m340 and unity programming and magelis. I have never seen such an awkward programming. No wonder modicon is losing the market share.

What type of Modicon is, Ethernet with modbus or Ethernet with can open?
What types of first and second HMI magelis are?

m340 2020, plc with xbtgt1350 touch panel