You cannot flash just any J400M combination file; it must match the of the firmware currently on your device.
: Look at the "Build Number" in your phone's settings or the information displayed in Download Mode . The binary version is typically the 5th character from the right (e.g., if the version is J400MUBU**B**... , the binary is B or the corresponding number). You cannot flash just any J400M combination file;
: It can resolve software issues such as "Hang on Logo," recovery mode loops, or corrupted IMEI information. if the version is J400MUBU**B**...