If this was a proper drug test, then the sample would have been sent for a confirmatory test to exclude any false positives. If that was not done, then not a valid test. We are talking about GC/ MS testing, so find out if this was done.
Amoxicillin has been known to cause a false positive test, as has advil.
However, this would be corrected by confirmatory testing.
So, there are three possibilities
a. you did cocaine
b. a false positive without confirmatory testing being done
c. Lab error, such as mixed up samples.
OK, so that is an initial answer….
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