i would suggest you tell them to check your levels. often times they will record the thc levels on a failed test. they should be able to determine by your levels that you have not smoked again.
smoked a blunt about 5 weeks ago. haven't smoked for 6 months before that. how did i fail urine test? . i am on probation for manufacturing and distributing marijuana even though i had less than 3 grams on me. i failed a urine test last month after i smoked a joint at a party. i failed that month. i haven't smoked since then but i still failed my urine test this month! .