Error reading Prometheus: Metric request error

[robingerold]

• What Grafana version and what operating system are you using?
  v8.3.4 / Ubuntu 22.04.1

• What are you trying to achieve?
  Adding Prometheus as Data Source

• How are you trying to achieve it?
  I installed Prometheus, Blackbox Exporter and exporter_exporter (reverse Proxy, so i can export all with one port)

• What happened?
  When adding Prometheus as a data source, it shows an error message

• What did you expect to happen?
  Data Source is working

• Can you copy/paste the configuration(s) that you are having problems with?
  

  

• Did you receive any errors in the Grafana UI or in related logs? If so, please tell us exactly what they were.
  

  

• Did you follow any online instructions? If so, what is the URL?