It's actually easy and straight forward.
just navigate to your .m2 folder.
.m2/repository/org/apache/maven
inside this maven folder, you will see a folder called Archetypes... delete this folder and the problem is solved.
but if you don't feel like deleting the whole folder, you can navigate into the archetype folder and delete all the archetype you want there. The reason why it keeps failing is because, the archetype you are trying to create is trying to tell you that she already exists in that folder, hence move away...
summarily, deleting the archetype folder in the .m2 folder is the easiest solution.