Asus x008da mt6737m secure boot da files

Wait for phone...
Phone found! [ 8 ]
Sync...
Inital Boot Ok!
BB_CPU_PID : 6737
BB_CPU_NME : [MediaTek] MT6737M|MT6737_S00
BB_CPU_EXT : 0xCB00 , 0x8A00 , 0x0000
Processing BROM stage
Settings for BROM configured!
SecCfgVal : 0x01000000
BromVer : 0x00FF
BLVersion : 0x0001
PreLoader : Active [ Boot with PL ]
BootLdrSS : SIGNED with SPRELOADER
Processing DA stage
DA Select done, will use MTK_AllInOne_DA_v3.3001.00.00
Sending and initialize DA ...

[DA_ERROR] : SECURITYBOOT_BOOT_NOT_ACCEPTED
Boot Error!

Operation Failed
Elapsed: 00:00:04
Reconnect Power/Cable!