Unfortunately email warnings about suspension is coming from the satellites when your node become online. This is a complicated issue, and we want to offer do not relay on our emails warnings, use the [Tech Preview] Email alerts with Grafana and Prometheus instead.
Regarding online score - it’s dropping when the satellite could not contact your node for any reason, each satellite do it independently, so your node may be online on one satellite and offline on another (for example, your or ISP firewall blocking incoming traffic from that satellite).
So, I would recommend to check your and ISP firewall settings and logs and make sure that they does not block traffic to/from your node for specific IPs or something like that.