Data source error with no text

I’m new to grafana and I’ve a textless error when adding a new data source.

I have a VM running prometheus / node_exporter / grafana, I created the data source and imported a dashboard and it works just fine.

However when trying to add a data source for another VM of mine (running node_exporter) I get a textless error:

Although I can clearly see & query the metrics when checking prometheus’ web interface.

Thanks for any help

what is the solution