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Recently done a iPhone X screen replacement for my partners phone, originally was having some battery issues when it was first replaced, so took the phone apart reseated the connectors and it worked fine. Couple of weeks down the line the iPhone X is now depleting its battery very quickly, and will suddenly turn off at 20% and sometimes will turn back on, or sometimes it needs charging to turn back on. This morning it had 100% and depleted down to 20 and turned off, and then on restart had 10%, and then it required power to turn back on, with the battery at 25% (2 minutes later).
it is 100 % battery issue . check your bettry health is settings .
