Default TWRP 2.7.1.1 over 30 minutes restore

Guys need your help
i flash Mahdi rom
then Purity rom

i've been backup before my stock 4.4.4 rooted rom (bootloader unlocked)
i using twrp 2.7.1.1
then i try to restore my backup it's over than 30 minutes still on "restoring system" until now still stuck on that.
i've been wipe data, cache, dalvick before restore.
even on flashing rom i doing that.

until now still on "restoring system" won't finish yet. is it normally?
what should i do now?