DevEUI for Heltec WiFi Lora 32(V2)

How can I get DevEUI for Heltec WiFi Lora 32(V2). Does it come with factory provided DevEUI ? If not, how can I assign a DevEUI to my various Heltec WiFi Lora 32(V2)?

DevEUI is set bu yourself:|

OK, Thanks,
I will try to do this way and then I return the result.
Best Regards, (by AntonioC)

Being set this way, by ourselves, how is made the control of this number/registration, to avoid double registration and then problem with function?

When registering, if EUI has been registered. The server will return the error message “deveui is already registered”

OK. Thank you again.
I will test and return the result.