[Windows Central Question]

Make the phone rest to default like you would but it or of the store

[Saijin_Naib]

Have you tried searching the web yet?

First link...
MICROSOFT Lumia 640 - How to Hard Reset my phone - HardReset.info

[Chintan Gohel]

Make the phone rest to default like you would but it or of the store

Factory Reset is Done through Settings > About > Reset your phone (8 & 8.1) or Settings > System > About > Reset your phone (W10M).

• You should see the spinning gears and your phone will reflash the last OS version held in recovery. You do lose data, but get your phone back. Sign into your Microsoft Account and restore your backup during the set up.

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