Need sample code to have multiple modbus clients on the same modbus server port (502)

Hello,  
I'm having a problem on a simple modbus server architecture (S7-1214C) and 2 clients.  

Only one Modbus client can connect to the S7-1214C Modbus server. 

I have control with the modbus doctor (modbus client), I have the same problem. 

When I run the second modbus doctor, I get the following error message: Port unavailable: 10.33.2.222  

This means that on S7-1214C,only one modbus client ?  


I have attached my modbus soft.

Regards.

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Update:
Thanks to this topic https://support.industry.siemens.com/tf/fr/fr/posts/single-modbus-server-with-2-slaves-clients/188846/?page=0&pageSize=10

and

https://support.industry.siemens.com/cs/document/34010717/which-ports-are-released-for-modbus-tcp-communication-and-how-many-modbus-clients-can-communicate-with-a-simatic-s7-pn-cpu-as-modbus-server-?dti=0&lc=en-WW

I have created a second modbus server on ​different port. It's working for 2 clients. 

unknown user

All Modbus clients access the Modbus server via Port 502.
In this case, it is necessary to have constant job-controlled establishment and clear-down of connections. The Modbus server can communicate with only 1 Modbus client through Port 502 at any one time. The connection to the first Modbus client must be cleared down and Port 502 released before another Modbus client can access the Modbus server. As soon as Port 502 is released, another Modbus client can access the Modbus server via that port.

Have you a sample code to have multiple modbus clients on the same modbus server port (502) ?

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