When a user is using their Hisense F10 mobile and suddenly the phone just stops at the logo, it is called the "Hang on Logo" problem. This is usually a sign of a system partition corruption or a boot file issue. In such a situation, if you try to flash with SP Flash Tool, the tool may fail without the DA Auth File. This file gives system-level permission to SP Tool to bring the phone back to life by overwriting the corrupt files. Sometimes the IMEI number is missing in Hisense F10 mobile due to which neither SIM works nor calls are received. This problem is a sign of NVRAM or NVDATA corruption. If you flash the correct files using DA Auth File, then it is possible to restore the IMEI. Because NVRAM files are not overwritten by normal flashing, only the DA file allows SP Tool to access these protected sections.
Have you ever connected your Hisense F10 mobile via USB and it only shows as "MediaTek Preloader"? This means that the mobile has been "bricked". In this situation, no flashing is possible without the DA Auth File. This file gives the tool access to the "BootROM" from which the phone can be rebooted. This file gives new life in situations where all other methods have failed.