Hi Wilas,
I had the EXACT same problem and all the Samsung technicians couldn't help me. I fixed it myself after a few hours and this is how I did it. Keep in mind that this will take a few tries as it's quite difficult and you need to get lucky.
First thing to do is to reboot the device. If you follow the green prompts at the top you should see, "VOL_DN + POWER_KEY for 3s" this means you need to hold down the volume down button and power button at the same time for 3 seconds. Do that. Now, once the phone boots up you only have a few seconds to boot the phone into safe mode, so start holding down the power button immediately until the option to shut down appears. Press and HOLD the power off button until another button appears named safe mode. Press it.
Now the hard part is over.
Your phone will now reboot into a mode where not many functions work, this will prevent it from crashing again.
1. Go to the phone app and dial *#9900#.
2. Turn the debug level to low. Your device will restart
If the level changes.
This should solve your issues.
Hope it helps!!