according to MacRumors According to reports, Apple has recently sent a memorandum to its retail stores and authorized partners, asking it to no longer provide repair services for iPhones that have been flagged as missing by the internal MobileGenius / GSX system.This probably means that the technician needs to GSMA Registration RepositoryVerify the associated IMEI code. In this repository you can find registration data for lost or stolen products.
Previously, Apple would deny repairs to devices that mightn’t disable the Find My iPhone feature, and the new policy further expands the crackdown on illicitly obtained devices. Under its influence, the risk of buying second-hand products from unofficial channels will become greater (you may buy stolen goods that cannot be officially repaired), but correspondingly, this may also prompt relevant users to turn to third-party products that are not certified by Apple. Third party repairer.