About retention and node discovery profile


we have a problem with discovery profile, we have a ticket opened about the issue but we have no answer. 

Basically we do discovery by customer subnet. What happens is that this discovery profile disappear after some time. 

We do not know why?   

Is it this related to the following parameter "Discovery Retention days Discovery profiles will be deleted from the database after configured days" inside "Orion Polling Settings" ?

We need the discovery profile to be permanent since customers add or remove devices. Redoing the discovery profile is not an option for us.

If someone has an idea or a clue I will appreciate it.