Isue after build

[davidsanchesgomez]

Heloo, I`m planning on using your IoT Traffic generation to be able to execute mqtt and coap traffic for a project.
When I was doing all the steps of the instalation guide I encounter a problem after building the program. When I run it and the window appears to enter a new UseCase, no matter what I put in the box name, it is telling me that the name already exists.

Also un General Messages in qt Creator i see this two lines, i don`t know if they are realated whit the error above:
-Project ERROR: You need to set the ANDROID_NDK_ROOT environment variable to point to your Android NDK.
Could not read qmake configuration file /home/david/Qt/5.12.3/android_armv7/mkspecs/android-clang/qmake.conf._

I hope you can help me to find the solutions

David