I have Lumia XL 640 device. The device has 1GB RAM. Mr problem is that the my phone take much time to open & resuming. Although my phone has latest updates installed like windows 10. please guide me.
Make a backup and then go to Settings > System > About > Reset your phone. This will reflash the OS version held in recovery. It should smooth out your device. This is especially true if you just upgraded to W10M. You may restore your backup, or even better if you don't and you do setup by hand. This is like getting a clean install.
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