Push messages

I have 4 cameras connected to a NVR. Two of the cameras push events to the HikConnect app the other two dont. The NVR is set up correctly with all cameras set to notify surveillance center .
Events work on the email though.
Do only some cameras support push messages?
I have 2 DS-2CD2042WD-I cameras which work. And Two DS-2CD1341-I cameras which will not push events.
DS-2CD2042WD-I - push works on line crossing, intrusion and motion - also emails events
DS-2CD1341 - Only emailing events
Any...

Push messages