Train button fails when selected period with time picker "from is invalid expected absolute or relative time"

[toni-moreno]

When trying to send a train with a previously selected period of time from the "Train" button in the LoudML panel, grafana sends this request to the loudml with error response.

loudml_1   | 172.20.0.3 - - [2020-07-30 07:19:08] "POST /models/linux_metrics_cpu_mean_usage_system_host_oss_mon_influx1_time_5m/_train?flag_abnormal_data=true&from=%222020-07-23T13:33:51.364Z%22&output_bucket=oss_mon_influx1_loudml&save_output_data=true&to=%222020-07-29T04:25:16.547Z%22 HTTP/1.1" 400 181 0.002027

And this is the error