If it is required of you by your employer, specifically needed for your job, your employer must pay you for your time. Generally, on the job training is compensable time.
They say you get what you pay for, and this response is free, so take it for what it is worth. This is my opinion based on very limited information. My opinion should not be taken as legal advice. For true advice, we would require a confidential consultation where I would ask you questions and get your complete story. This is a public forum, so remember, nothing here is confidential. Nor am I your attorney. I do not know who you are and you have not hired me to provide any legal service. To do so would require us to meet and sign written retainer agreement. My responses are intended for general information only.
Mr. Kirschbaum is correct. Any time you are required to be at work you must be compensated. Your employer can require you to come in on your day off, but you must be paid for that time.
Good luck to you.
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Ecountered this a day ago. A home health worker performed 12 hours of service as an"audition" and was rejected. The employer said this was not a paid day because they wanted to see her skills. Following the previous posts, it must be upfront and in writing. I concur with my esteemed colleagues.