Apple has announced that certain iPhone 6S or 6S Plus units may power down unexpected or uncontrollably. The company has noted that this is due to a "component that may fail", although it failed to mention which one precisely. Accordingly, it has started a problem by which affected users can have their devices repaired.
The products in question were those made between October 2018 and August 2019. Those with 6s or 6s Plus phones from this date-range can check whether their devices have the defect in question by checking their serial numbers against an Apple database on this page. Should this result in a match, a user can arrange to have their iPhone sent in for servicing.
Their maker has stated that this will be done free of charge. To avail of this, the user needs to arrange to have their device sent to the OEM. A user can do so by going to their closest Apple Store or authorized service provider. Alternatively, they can arrange to have their device sent to an official repair center by mail.