Trouble with time series data from a SQL server data source with Grafana

Hi I am trying to represent the number of parking spaces in a graph visualisation against the timestamp it was recorded.

This is my current code:
SELECT
SpacesAvailable as value,
$__timeEpoch(CurrentTimeStamp)

FROM
  ParkingHistory

Some examples of the data the SQL table holds are below:
SpacesAvailable : 483,323,876,754,234,665

CurrentTimeStamp : 1570041001.85894, 1570049102.77719, 1570061702.10032

I don’t get any errors but no data is visualised.
Any help with this would be much appreciated!