WAN interface fails

[Peter847]

I have a two Opnsense systems, one connected to an AT&T VDSL gateway and the other an Xfinity cable gateway.  Periodically the WAN interfaces or each one fail, this seems to be linked to when the provider resets their gateway and/or updates the public IP address.  Both Opnsense systems are setup up in their gateways' DMZ.  It appears that the gateway goes down for a few minutes, usually in the middle of the night, that breaks the WAN/internet communication but Opnsense does not recover when the internet comes back up.  Rebooting Opnsense cures the issue.  One system is in Chicago and the other in Boston but I can only be in one place at a time, hence this is a problem!

As this is the same behavior on two different gateways, I am thinking it is an Opnsense issue.  Any thoughts on where I start looking?