How to fix redmi note 9 pro all these problem?

Why redmi note 9 pro drain battery so much after 5 year use also lag so much while gaming and make wired sound now it restart on the video call every time.So what can I do about it?

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@nahidyeami13928 what have you done and/or check so far?

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@oldturkey03 I had played many game on my phone,visited many website and reset my phone about 2 time

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@nahidyeami13928 start off by replacing the battery. Tell us about the wired sound and the restart on the video call

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