I think the answer is yes, but there isn't enough info in your post to say definitely. I would not assume that your PO doesn't know how to do his/her job. It would help to discuss the matter directly at this point.
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I believe you are talking about a test that came back dirty prior to you getting a prescription from the doctor. So yes if you used meth while on probation and tested positive for it they can and will violate you. You will need an attorney.
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