UPDATE:
The seller got back to me and suggested that I sand the affected area lightly with sandpaper to check whether the carbon fiber itself is damaged or if it's just a surface-level cosmetic issue.
If the carbon is actually compromised, they said they would send me a new frame (although it’s not entirely clear whether I’ll have to return the current one).
If it turns out to be only cosmetic, they offered to cover the cost of repainting.
We’ve been talking through AliExpress chat so far.
Do you think I should ask them to confirm everything by email, just to have it in writing in a more official way?
What do you think about these options?
Does this sound like a reasonable approach?
What would you do in my place?