Thank you for trusting your question to JA today. I am a licensed attorney with over a decade of law practice and over 20 years of experience in the legal field. I’m happy to be of assistance.
Lunch period is not legally required under federal law. You didn't list which state you are in. If your state doesn't require a lunch period either (and many states don't), it's not illegal to disallow a lunch period. If your state does, then you just need to report them to the Department of Labor for your state.
As for the discrimination you mentioned, you didn't really state how it is discrimination. Yes, being treated differently than other people is part of discrimination, but you also have to be alleging an illegal motivation.
So, you said two others are their favorites, but two of you are always getting picked on. Why? For it to be illegal, you have to be able to say (and show evidence) that you are being treated differently because of race, religion, gender, age (over 40), disability or medical leave use. You've not mentioned any of these things. If you can allege one of these, then you need to file a complaint with the EEOC in your state, alleging discrimination.
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