If you are facing repeated USB connection fails, then the absence of the DA file could be the reason, especially in phones like INFINIX SMART 5 X657. Flashing of INFINIX SMART 5 X657 phone is only possible if we give the system the authorization that the DA file provides. When you cannot access recovery or fastboot, and the phone only blinks, the DA file creates a path that makes flashing possible.
The biggest problem during flashing comes when the mobile is not detected by SP Flash Tool. This problem is common with secure mobiles like INFINIX SMART 5 X657 because they have secure boot protection. The only solution to break this security wall is the DA file. Without this file, the tool always gives messages like failed to download or authentication error. But as soon as the DA file is added, the tool not only detects the mobile but also gives you full root access so that you can reconfigure the firmware, nvram, or imei sections.