Hi Abenezer,
Thank you for sending the URL. This was a bit of a puzzle to solve!
SAM makes the API call with no 'utc' parameter, so it is set to the default 'utc=false'. Your URL sets 'utc=true'. If you compare the data between the two files, you should see the data is offset by the difference between UTC and local time.
Note that there are two similar WIND Toolkit API endpoints that appear to return the same data in different formats.
They also have different default values for the 'utc' parameter, so if you happen to be working with the 'wtk-download' endpoint, be aware of that difference:
developer.nrel.gov/docs/wind/wind-toolkit/wtk-srw-download/ (this is the one SAM uses, with "srw" in the name)
developer.nrel.gov/docs/wind/wind-toolkit/wtk-download/ (this one returns CSV files)
Best regards,
Paul.