It sounds as if you have a legitimate complaint, but we need more facts to understand your situation. I can't tell whether or not it is mostly an immigration question or a labor one. Please give more facts. Good Luck.
Paying for your H1-B expenses does not excuse them from paying wages for work. Contact a wage and hour attorney. It may be wise to also sit down with an immigration attorney as well to discuss how this may impact your status as well.
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