Possibly tense? Since "me arreglo mi pelo" is "I fix my hair" it seems more grmatically correct to say "me arreglé el pelo" or "i fixed my hair" (past tense) ???
The mistake is that it says “I fix my hair,” and not “I fixed my hair,” because arreglo is fix and fijado is fixed. If that helps. It would be better if you explained it better.
