Remote viewing of security cameras

[skunked again]

Until recently, we've been able to view our cameras remotely. Now they're only viewable when connected to wifi at home. I emailed zosi, who made the dvr\cameras. There response was to ensure ports 80, 5000, and 5001 are open. How do i do this? The router is a netgear , model R6400v2.

[Barnacle Bill]

See if this helps. Open Ports on a Netgear Router(TCP/UDP) - VisiHow

[skunked again]

Thank you! I'll try that. I'm wondering if the router had an update? We have some cameras and a nest doorbell, all was well. Now neither can be viewed remotely.
I wasn't aware of nest not working either, until after I posted this thread.