Default TWRP 2.7 crashed after wipe and cant start TWRP again

I need help. I have B510 and installed TWRP 2.7. I wiped to install omni rom. But after wipe TWRP crashed and dont start again. Now i cant go back to B510.
Huawei Ascend P6 / Quad Core 1.5GHz / 8GB / 2GB RAM

Screenshots of the B510 Android 4.4.2 Beta: