How to fix the unable to mount SD card problem in my brand new Android phone? I had just recently bought Asus Zenfone 4 and until yesterday it was just working fine. All of a sudden on yesterday the phone started to behave weirdly and settings was not at all opening. I thought may be a reboot would do. Hence I tried to reboot and since then I had been stuck at the Boot screen only. 
I tried to pull out the battery several times but apparently that did not work out. 
Then I decided to to hard reset and tried to go to the boot menu using Power Button + Volume Up combination and did it twice consecutively . But that too did not solve the problem.
At last I opted for SD Download(I do not have a SD card) and encountered this problem.
it also said unable to open debricking.

I badly stuck . Please tell me and explain me what to do. 
Any help will be much appreciated.
standard stuck, just download your stock rom whose extension is tar.md5 flash it with odin to your phone when your phone is in download mode (volume down + home + power)
if you can enter the recovery mode just try to factory reset which mostly solves bootloop