Battery drops from 40% to 6 % in a few seconds

[Carl Muller1]

I have Acatel idol4s phone running Windows 10 mobile. When the phones battery reaches 40% it then jumps to 6% in a few seconds. It's a built in permanent battery. Can I fix this.The phone is only about 2 years old. Mint and works very well Please advise. I still like windows 10.
Thanks,
Carl

 

[skald89]

How is the battery life till it reaches 40%?

 

[Carl Muller1]

Battery goes down to 40% normal time then
Within a minute jumps to 6%. Someone said it might be one of the windows Updates?
Don't know

 

[skald89]

Which build are you running?

 

[Peter Burns]

my 1520 did this changed the batt and all was fixed