Hi,
Try to give full access to this new users... Check whether the newly created users has permission same of the users with production systems... I mean the administrative rights & privileged.
You can just delete only the users..There wont be any problem when you delete the newly created users..
Dont delete the Production system userID.. Just delete only the new system user id..
I strongly feel like permission issue would be root cause for your issue.
You can give a try.
Thanks and Regards,
Vimal