I am owner of M2 mini since December 2015. I bought it from a Chinese eshop through internet. This device according to its box label, is model M578A.
It came with and runs on Flyme OS 4.5.3I.
Several times I got notification that an update is ready for downloading.
I tried many times to update my phone and every time I get the “firmware corrupt” message.
I have no idea if my phone is a Chinese version, or an Indian version.
It might be of Indian version, because on the calendar app has, almost by default, the Indian holidays.
So kindly I ask for your help.