Hi,
I install latest xiaomi.eu_multi_MI6_V10.4.2.0.PCACNXM_v10-9.zip on my phone, but it take too much battery, so I decide to back to xiaomi.eu_multi_MI6_V10.3.1.0.OCACNXM_v10-8.0.zip.
So I use latest twrp 332-1 - clean all data using Format (like always) .... (additionally in 2nd try I clean...