unearned steam badge

sorry i only just noticed this but i have the steam badge "untouchable". you get this badge from playing in a hardcore league and defeating the eternal labyrinth. i don't think i have ever played in a hardcore league and i KNOW i have never gotten any hardcore character up to the point that they could complete the eternal difficulty of the labyrinth. it says i completed the task at the exact same date and time down to the minute (back in 2017) as 6 other badges that i did earn but i completed those tasks well after the time stamp on the badges. i do not have any other badges related to hardcore modes.