I keep getting HTTP 401 Unauthorized messages*
This means that the given username/password combination is incorrect. Note that
if you created your account recently it could take a while (a few days?) until
you can use that account on apihub and therefore
sentinelsat too. You can go
here to test access on the apihub endpoint.
The query fails with HTTP 500 connection timed out
SciHub servers are known to have outages due to high demand, try again later.
Query fails with ‘Longitude/Latitude is out of bounds, check your JSON format or data.’
Standard GeoJSON specification contains only WGS84 format, check if your data complies with it.
My search returns 0 results
Maybe there are no images for the specified time period, by default
sentinelsat will query the last 24 hours only.
Make sure to check the issues on GitHub too.