Reinstalling the official firmware (Stock ROM) on the Vivo Y71 (Model PD1731F) can resolve issues like boot loops, software bugs, andIMEI corruption. The latest firmware (PD1731F_EX_A_1.19.2) can be installed via local upgrade for functional devices or using the QFIL tool for unbricking. For more details, visit Vivo Support Y71 Funtouch OS PD1731F_EX_A_1.19.2 System Update - Vivo