It could have have a damaged connection on the battery I would take it off and check the connections and clean the connectors. Also check the capacitors next to the battery connector.
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It could have have a damaged connection on the battery I would take it off and check the connections and clean the connectors. Also check the capacitors next to the battery connector. You should also check the lightning port. Here is a video that shows what I was talking about.
It could have have a damaged connection on the battery I would take it off and check the connections and clean the connectors. Also check the capacitors next to the battery connector.