Thank you for reaching out.
The runtime of a power station depends on the power consumption (wattage) of the devices connected to it. If higher-power appliances are used, the battery will deplete more quickly.
Could you please let us know the wattage of the device(s) you are using? Once we have this information, we will be happy to help you check whether the performance is within the normal range.
The inverter itself consumes some power during operation — about 12W of standby draw. When you're using a small load like a 36W fan, that inverter loss takes up a bigger percentage of the total output, which can make the usable capacity feel lower than expected.
Please rest assured that if there is any quality issue, we will take full responsibility and assist you with a proper solution.