It’s easy to understand why a phone’s battery percentage is inaccurate as there are many variables that can affect your battery’s current readout. Here are some steps you can take to make sure your phone’s battery percentage matches reality:

1. Check and recalibrate your device’s battery-level tracking. This could help sync up the battery readout with the actual energy remaining in the battery.
2. Uninstall any third-party app that could be affecting battery readouts or possibly draining your battery.
3. Turn down your device's screen brightness if it's set at maximum.
4. Make sure you're running the latest version of the operating system and all the necessary updates to improve efficiency and accuracy.
5. Make sure your battery isn't overheating.
6. Try booting your device into safe mode if the battery readout is still inaccurate. This will stop any third-party apps from running – which could be the problem.