If your sample is cross contaminated with fentanyl e.g. from a scale there is a chance the portion of the sample you sent for testing doesn’t have any fentanyl.

If your sample is cross contaminated with fentanyl e.g. from a scale there is a chance the portion of the sample you sent for testing doesn’t have any fentanyl. These aren’t homogeneously mixed substances its someone loading a dime bag in a bedroom.