If your Xperia™ device doesn't respond when you try to turn it on, try these actions one after the other. Verify after each action whether the problem was solved before trying the next one.

Allow your device enough time to start. Press and hold down the power key until the device vibrates and then release it. It may take up to 10 seconds before the device vibrates.
Make sure that your Xperia™ device is charged. If the battery is drained, it may take up to 30 minutes for your device to respond to the charging. During this time, the screen remains dark, not showing the charging icon. Also note that it can take up to 4 hours for a drained battery to charge fully.
If you have trouble charging your Xperia™ device, start by making sure that you are using an original Sony charger and a USB Type-C cable specifically intended for charging your device. Try to charge the device with a different USB cable connected to the USB port of a computer. If the device starts to charge, this may be a sign that the charger is not working properly.
If there is a memory card in your device, remove it and restart the device. If removing the memory card solves the issue, your SD card may be damaged. In this case you need to get a replacement SD card for your Xperia™ device.
You can force your device to restart or shut down in situations where it stops responding or won't restart normally. No settings or personal data get deleted during a forced restart.
If a forced restart procedure doesn't succeed, you should try the 2-minute restart procedure.
Use the Xperia™ Companion computer application to perform a software repair to reset your device. Note that all data is deleted from the internal storage of your device when you perform a software repair. Content that you have saved on an external SD card, such as photos, videos and music, is not deleted.

topic Re: help me please! it's very impotant! in XZ Series

Cant power on my device

Re: help me please! it's very impotant!