Moto G2 battery unstable behaviour

[Dipak6]

As the screenshot shows:

Battery level dropped from nearly 80% to zero in an instant.

On charging, the battery level just jumps to variable levels if I disconnect and reconnect the charging cable.

Several chats, emails, calls from Moto support. Advised to factory reset. 

But looking at some answers here i am having doubts about going in for that drastic option.

I wish I could attach two screenshots. The text editor only lets me attach one

[Agent_JM]

Hello Dipak6,

That's odd. Try calibrating the battery first. We do recommend these steps to re-calibrate the battery. Press and hold the power button until the screen turns off. The phone will reboot then on its own. Charge the phone to 100% and then leave it on the charger for a few hours. Let me know if it helps.

Regards,
JM
Motorola Support

**Please don't ask me questions by Personal Message; questions belong in the forums.

[Dipak6]

Dear JM

Thank you very much for your kind answer. I will try that right now and revert.

Just a small point - the original charger for my G2 was damaged, so I purchased a replacement (Sony) which I think is a fast charger.

Could using that create  this problem?

Would it be okay if I use a Moto G3 charger, or the Sony charger for the battery calibration procedure you advised?

Thanks

Dipak