Review the item:
Cindy's mumbling often gets her in trouble just
the other day, her stylist misunderstood Cindy's instructions and dyed
her hair blue after Cindy asked him to trim the ends.
The problem occurs between trouble and just. Cindy's mumbling often gets her in trouble is a main clause, so it can stand alone as a complete sentence. Just the other day, her stylist misunderstood ... begins the next complete sentence.
Because these two parts have only blank space between them, they make a fused sentence, a major sentence error.
To fix the problem, you could put a period after trouble and then capitalize the J for just.