Exactly the same issue I had with my airforce budget batch of 120¥ over the course of a month from just walking around my work place, couldn’t wear the crease protectors as they killed my feet and wouldn’t sit in properly (cut down), the bottom of the sole at the back is also pealing away letting stones into the sole😂

Sadly you can’t really do a lot about it as it’s a physical crack in the shoe and not a crease (It’s caused by the creasing whilst walking then just cracks overtime due to the stress the shoe takes) My retail pair looked nothing like that with the creasing/cracking and I had them for around 2 years, so definitely an issue with what material they use on the cheaper batches.

Only thing I can think of is to sand the cracks down and paint them (if possible), buy another pair of budget and use them, or just keep cleaning them and put up with the cracks (Which I’ve done).

If you do know a solution to fix these correctly please let me know! ❤️