Are all the values the BMS reads from the cells and sensors within the limits the BMS has been set to? If any of them are out of range, the BMS may be setup to prevent discharge to protect the cells.
If the cells are actually all ok, as are all the sensor readings, but it's just the limits that are wrong, you can change the limits so the cell values or readings will then be within the limits.
The most common problem that causes this is a difference in voltage between cells, usually greater than 0.1v. (depends on the BMS's settings or design), but your screenshots indicate this isn't the case here.