Start by making pairs to see if you can find a pattern

a8 bd ac c6 cc bb ba ab ba bc ab b6 b0 b1 cc cc cc aa b0

Notice where the numbers position should be in the passcode format, they all start with C

This looks like Hex Atbash

Your index is

0123456789abcdef

fedcba9876543210

57 42 53 39 33 44 45 54 45 43 54 49 4f 4e 33 33 33 55 4f

Convert hex to Ascii

WBS93DETECTION333UO

Looks like a keyboard flip except for the question mark. So q=p, a=;, z=/

atu82?942gb

? could mean “question” but we use keyboard flip. Reverse of question is answer

atu82answer942gb