openwrt https-dns-proxy on the router has stopped working - This device is using NextDNS with no profile.

At some point in the last few days, my whole-house router-based nextdns setup has stopped working.

For the past several years it has been operating perfectly via the openwrt https-dns-proxy configuration at router level, (meaning every device on my network benefits from the ad-blocking etc).

Without any changes at my end, I noticed that sites were suddenly riddled with ads. Upon checking the nextdns dashboard I see that my profile is now being ignored.

I'm a paid subscriber.

Here's the https-dns-proxy config - note profile ID suffix on the resolver URL.

Output from test.nextdns.io

The router dns has stopped working so TVs and Alexas and the like are no longer benefitting from the NextDNS service.

I see several recent reports of the same warning, but at device level.  This is at the router level.  It feels like something outside of my network has broken or changed. 

Please advise.  Thank you.