NCM job completion notification emails not being received from 2 pollers

we have network devices dsitributed across 4 pollers ( 1 primary and 3 additional). we are running a NCM nightly backup config job daily to download the running config from devicea dn job completion emails are being received from just 2 pollers and we are not getting emails for the other 2 pollers including primary.

could anyone help me in resolving this issue. I ahve alreday restarted the jon engine services on both the pollers for which I am not gettting the results from. however when I got to the pollers to NCM to see the running config status I see backup is taking place but I am not receiving the status of those 2 pollers.

Please hlp me in resolving the issue.

Thanks

Akansha