As a note: it doesn't matter that she is African American. Only that she had very hard coarse hair. I say this because it becomes a conversation that is based on ethnicity and it should be a conversation based on hair.
Now: wax her every 4 weeks with really good techniques. She needs to use home care, Body Polish Kit and Clear It. With this type of reaction it is CRITICAL that the client comes in super regular and uses home care. And of course, you must use good techniques.