New host on Prometheus not showing in Grafana

Hello,
I have set up a new host with windows_exporter.
host-ip-adress:9182/metrics is showing the metrics
I added a new host via prometheus.yml
On the prometheus web interface I can see that the host is up and can query it.
In Grafana, when accessing the data source, I can see all hosts except the new one.
What am I missing?

are you still encountering this error or is your new prom instance now showing up?