Concurrent Manager not running

I am new to EBS and we are running 12.1.3 version.

The developers are trying to develop reports but when they sent request and the status shows no manager.

How can I stop/start concurrent manager?

I checked the status and it shows the following:

You are running adcmctl.sh version 120.17.12010000.5

Enter the APPS username : apps

Enter the APPS password :
Internal Concurrent Manager status could not be determined.

adcmctl.sh: exiting with status 0

Then I query the database, I got the following:

Concurrent Manager's Name                      TARGET Processes ACTUAL Processes
---------------------------------------------- ---------------- ----------------
Standard Manager                                              6                0
Internal Manager                                              1                1
PA Streamline Manager                                         1                1
Inventory Manager                                             2                2