If you press PF1 you will get this long message "NO ENVIRONMENTS MATCH OR USER NOT AUTHORIZED TO USE THIS ENV".
When you enter a line command next to the member Endevor looks for the information. Endevor looks in the Endevor Environment you are currently using. Endevor will look to see if the Environment exits as in the footprint has it. Then it will see if you have security access. If not then the error message is shown.
Common causes of this message are that you don't have access to the Environment,the Environment was re-named, deleted or is on another C1DEFLTS.