Earpiece speaker

I have been using this phone since 5 years, working flawless without any issues. About phone everything is working fine , face id working, no dent or scratches, earpiece and speaker loud as original for calls and entertainment, except only issue being battery level at 77%, to be honest its very low as for my usage ,normally using social media and youtube on speakers i would say maximum around 3-4 hours. I refused to change the battery to keep phone in its original state and keep the waterproofing seal intact. OVERALL IF INTERESTED MSG AND FOR ANY OTHER QUERY FEEL FREE TO ASK.