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That may be owing to several types of problems. But for pretty much all of them, it would be best to resign yourself to doing a wipe and hard reset on the phone.
This will wipe all individual data and configuration off the phone, and all individual data/pictures/configuration, etc., on the phone, will be erased.
If you approve of trying this, I will give you instructions on how to go about it. Let me know, please. Thanks.