Dark line on heel of 2016 bred 1s?

[Ammo1337]

Apologies if this is not the right place.

I keep most of my collection clean but I've noticed this dark line on the heel of my breds? Is it possible to remove? The camera doesn't quite catch it well and it's much darker than it shows up in photos.

I'm betting its probably due to humidity or something?

Any info or tips is much appreciated. Haven't had this problem with any of my other j1s.

 

[SteveSteve72]

Please use this thread https://niketalk.com/threads/official-sneaker-care-maintenance-post-its-back.15471/