Error in Grafana Alerting - Failed getting data source

We are running grafana 7.5.17 with postgres as backend and we are running into below alerting errors

lvl=eror msg="Failed getting data source" logger=sqlstore err=EOF uid= id=9 name= orgId=1
lvl=eror msg="Alert Rule Result Error" logger=alerting.evalContext ruleId=18903 name="<ALERT_TITLE>" error="could not find datasource: EOF" changing state to=alerting

Checked the database and the datasource is present in db in data_source table and also validated that the datasource is present in the api/datasources API response

For the alerts that had set If execution error or timeout as Alerting, alert is triggered with Error: could not find datasource: EOF

We are seeing this for all kinds of datasources - prometheus, elasticsearch, stackdriver and postgres

Why are we getting this error and what to do to fix this ?