Here are some steps to help resolve your phone’s battery percentage jumping around:

1. Check the application settings: Check the settings of all your applications to determine that no program is running too often or fetching data from the web.
2. Background App Refresh: Check the Background App Refresh settings to ensure that applications are not running unnecessarily.
3. Phone Settings – Check your phone settings – particularly the display brightness level and any settings relating to applications that refresh in the background.
4. Charge cycle: Try to reduce the amount of time your phone is plugged into any charger.
5. Battery optimization: Check to make sure any Optimization Settings are turned off.
6. Reset device: In extreme cases, the battery may need to be replaced or the device may need to be reset.

If none of these steps resolves your issue, it could be a problem with the battery itself or with the device’s chipset.