A:Answer A google search showed this:
If your iPhone only stops charging at 80% sometimes, it’s most likely due to a feature Apple implemented to extend the life of your iPhone battery. Apple introduced a battery optimization feature in iOS 13 that slows down how your iPhone charging, and even holds it at 80% to prevent over stressing the battery.
That’s why your phone sometimes charges, but then stops at 80%.
Most of us try to keep our phones as charged as possible, but as it turns out, this can be detrimental to your iPhone’s battery.
