nginx DNS doesn't update the upstream IP

[kay]

We tested with a default "resolver 8.8.8.8;" and "resolver 8.8.8.8 30s;"
options. Both keep using the outdated IP address until you run "nginx -s
reload". The upstream is AWS LoadBalancer, which changes IPs quite
frequently.

I'm using nginx 1.19.3. Any clue what could be wrong?

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,291252,291252#msg-291252