Likely not. You should consult a Business Law or Employment Law attorney licensed to practice law in Arizona (easily found on Avvo.com) regarding the wage and hour laws in the State of Arizona. You may find that a letter from the attorney to the employer can clear up the matter quickly. If not you may have to take the employer to Small Claims Court and get an Order from the court for any back pay erroneously taken from your paycheck.
As a general rule, if you're required to be available for customers during your work hours, then your employer must pay you for that work. You are almost certainly owed some overtime.
This answer does not constitute legal advice. I am admitted in the State of Arizona only. This advice is based on general principles of law that may or may not relate to your specific situation. Facts and laws change and these possible changes will affect the advice provided here. You should not rely on this advice alone, and nothing in these communications creates an attorney-client relationship.
This answer does not create an attorney client relationship between you and I. I am not your attorney unless we both sign a written contract that describes our relationship and terms of the representation. Any information provided to you here is not a substitute for the advice you need to pursue any legal matter. I advise you to retain the services of a local attorney before taking any legal action in this matter.