Why is my phone shutting off?

[AC Question]

When my note4 gets to 21% it cuts off like it's completely dead. Then when I turn it back on it shows it's at 0%.. what could be the reason for that it wasn't doing that before....

 

[belodion]

Welcome.

It could be that the battery needs replacing.

 

[Epicbk]

Thank you I will look for an original battery