Lenovo A7000 - Marshmallow - Couldn't erase SD card

Hello all,
I have recently upgraded my phone to Android 6.0
Everything worked fine until i formatted my SD card to Internal.
After the conversion, it was working well. I was pretty much satisfied. With that confidence, i moved all my apps from Internal to SD card.
After some minutes my phone got struck, so i restarted by removing and placing the battery in the back.
When it booted up it didn't detect my SD card and kept showing an error that, i need to Forget my SD card.
i googled the condition and found a post explaining the issue that it is Android 6.0's bug, and it's highly recommended to not move apps from Internal to SD card without a reboot, after converting the SD card to Internal.
The post also explained about wiping the SD card, as the only option left, and instructed to fastboot the device.

For some unknown reasons, the default "hold press Power button and press Volume Down" didn't work in my phone and it took me to a meta mode, where nothing is displayed apart from saying that it is a meta mode.
Then i took a wrong turn by repeating the same by pressing the Power and Volume Up button. It took me to factory mode, where i was displayed with 6 options in Chinese.

I can't read Chinese, and one of the option had an English word "eMMC", i thought this was the option to wipe out the SD card and selected it. It restored my phone to factory settings by erasing the Internal memory instead of the SD card.

Now, my phone detects my SD card, but shows it as "Unsupported" under Storage and USB option. And it asks me to Set Up the SD card by formatting it.

There are two options, "Use as portable storage" and "Use as Internal Storage".
If i select the first option, it says SD card is ready. But it doesn't format or fix the errors . And if i go for the 2nd option, it doesn't format and it displays the following error as a Toast.

Couldn't erase SD card
command '46 volume partition disk: 179,128 private' failed with '400 46 Command failed'

This is a Strontium 32GB class 10 SD Card. Kindly help me to format the SD Card and fix it's errors so i can use it again.