Why my battery show -2%

[sony85]

My battery shows -2%
either way is charging or not ?
What cause this problem?
Its a brand new phone

 

[678GUY]

it can be cause by a lot of stuff 1 if it cant dedect how much there is 2 if there is a problom with the battery 3 buged operating system tell me how it happand maybe ill be able to help you