Wipe data error - Unable to mount '/data'

[Aliagha]

Hi, Sorry for my bad English.

I have a "Huawei G610". And i flash wrong rom on it.
Now phone boots up but the "Encryption unsuccessful" page shows. And just has a button "Reset phone".

"TWRP" recovery mod is installed on phone and come up after tapping on Reset phone in prev step.
In TWRP i enter to "Wipe" and select " Wipe data - Factory reset " and i get this error:

< Unable to mount '/data' >

I back to TWRP main menu and enter to "Mount"
But "Data" is unselectable !

Please help me how to fix this problem

Thanks a lot !