You mention that this started happening quite recently, was it after something specific that this started? For example, installing a specific app.
You could try forcing your phone to shut down by pressing and holding both the volume up and power button at the same time until the phone vibrates, should not take more than about 15 seconds. After the device has shut down, boot it up normally. Is there any change or are you experiencing the same behaviour?
If so, could you try rebooting your phone to safe mode? That way we can rule out this being caused by on of your downloaded apps since they will be temporarily disabled until you restart your phone.
Let me know how it goes!
- Official Sony Xperia Support Staff
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