No data points / epoch length

I’m working Influxdb (1.7.6) and have found that the only way I can get a data point is if the epoch time is 19 characters long.

1558019231000000000 – works
1558019231 – doesn’t work

Does Grafana (6.1.6) have a config item that controls the length/precision it expects, or any other explanation for this behavior.