Hi my name is ***** ***** I will be the expert working with you today to help and resolve the problem you have posted.
I am sorry to know that you are facing problem with your galaxy tab.
How old is it and what have you already tried so far to fix it.
Its time to change the battery there is no point in doing any troubleshooting because the battery life is 2 to 3 years max however you have got a good battery usage till date as it lasted more that 4 years.
Replacement battery kit.
you can order battery online
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