[Windows Central Question]

I have done a soft restart as suggested elsewhere. No resolution. Any suggestions.

[Bobvfr]

Make sure you use the original "Mains" charger you got with your phone and I would leave it on charge for a few hours. If a battery is completely flat you need time and more power than USB can supply, as the phone will try to start and then the outgoings are more than USB can supply as the phone tries to sync.

Or it could just be a duff battery.

[Chintan Gohel]

I have done a soft restart as suggested elsewhere. No resolution. Any suggestions.

try with an external charger if you have one - the ones you can use to charge batteries outside the phone
Is it an original battery?

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