Zumba's Terrible service

I signed my daughter up to become a Zumba instructor. For the past few months, they have deducted ZIN membership fees, but we can't log in to her account, nor can we cancel the membership. I have sent numerous email emails without any replies. I expected a big brand to be more professional than that. I will not make use of any of their products ever again. Terrible service. I would like a refund for the past few months because I could not use the product.