Welp, now what???!! I’m so sorry this happened to you. I have no recourse for you either, just empathy!
But let’s work through this. Do you take any other prescriptions or OTC drugs? Because there are meds that can cause false positives.
Did you take any cough medication with codeine? Codeine metabolizes into morphine through its first pass through the liver.
How about any allergy med like Dimetap or Clairiton (Lortadine). That’s another drug that can show false positives in a blood test.
If you wanted to make a stink, which I might if I had no recourse, is demand a hair follicle test or repeat drug test.

Wow, to be cut off just like that without listening is really not fair. Were you trying to have a pain med refilled?