Hi,
Actually there should not have been any issue with the environment (what can be ? ) but it is definitely about it. We could not delete/copy the environment since it says "the users are not available" although non of them were actually added. However, we realized that the BPC roles are generated in BW system although we could not add them. We delete the roles manually and then we could copy the environment. Then we copy the environment and we were surprized since we could add the users successfully in the copied environment.
Thanks a lot