Abnormal access status to upstream server: Get 1.2.3.4: net/http: timeout awaiting response

I have a web server that is working fine through Safeline but I have this error.

"Abnormal access status to upstream server: Get 10.20.30.4: net/http: timeout awaiting response headers"

I will test tonight when traffic is light but I'm wondering this these lines in my Apache config may be causing the issue:

Header unset Server
ServerSignature Off
ServerTokens Prod

Just thought about those as I was submitting but figured I'd post anyway in case this helps others. I will test later and post any updates.

UPDATE: I removed those from the config but am still received this error. I is related to the upstream health check but I'm not sure why it's failing. I have multiple sites on the same server and they do not display this error.

Any updates on this? This seems to randomly show up on all my sites/applications I have on one server. Sometimes it shows the green check and others it shows the error. I'm running Apache on Alma Linux 10 with SELINUX enabled if that helps. Safeline is installed on the same network. All sites function fine, they just display the error.

On a side note, I have another server set up the same way running one site and I do not get this message on it.

Since overall services are not experiencing any anomalies, does that mean the backend application is receiving health-check probe logs from the WAF? Could you provide those logs? Meanwhile, you can run the following command on a machine within the same network segment to check the response latency:
curl -v -w "\nTime_Total: %{time_total}\n" http://10.20.30.4/