Load Balancer screenshot:
Is this legend refering to listener of LB or Backend server(s) ? I infer Backend server listener.
Documentation https://docs.public.oneportal.content.oci.oraclecloud.com/en-us/iaas/Content/Balance/Tasks/common_side_effects_health_misconfiguration.htm
We only support TCP and HTTP health checks. If your backend is using HTTPS, then you would need to use TCP as the protocol.
I believe some application force use of https (APEX may be one).
I believe Product legend should be updated to reflect documentation.