The answer from Payam Toloo, Owner of Payam Data Recovery:
If Apple cannot resolve the issue, it indicates damage to the logic board. Generally, Apple conducts diagnostics on components such as the battery and screen. Should the logic board be found irreparable or damaged, two options are available.
You may consider a local phone repair shop if data privacy is not a primary concern and the data itself is not crucial. Most phone repair shops perform basic repairs, such as addressing short circuits on the circuit board’s surface, replacing batteries or screens, or cleaning components with an ultrasonic cleaner. However, if these efforts prove unsuccessful, and a local phone repair shop cannot assist, we recommend bringing the device to us.
We specialize in data recovery and maintain a partnership with Apple, who recommends and refers their customers to us for this service, as it is not something they offer. Apple advises all customers to maintain iCloud backups to prevent data loss; however, should data loss occur, we can certainly assist. We can either temporarily repair the phone to back up all data using the correct passcode, or, in cases of severe damage, transplant the main components and memory chip in a “board swap” to another phone to retrieve the data.
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