There is not a shred of evidence that proves that Riboflavin causes false positives (or negatives). If such claims were actually true, then persons who consume cereals rich in Riboflavin (ie Total, Product 19, etc) would test positive for THC.
In actuality, there really are no false-positives anymore. False-positives are eliminated when a urine sample undergoes a confirmation GC/MS test.

but it was suppose to store it into my fat cells for upto five hours without it showing up in my U/A test.
If you take such claims from these detox potions at face value, then Ive got a planet in another solar system that is for sale at a flea market price

ALL detox drinks "work" because of dilution. That means they "work" because of the water that youre required by the instructions to drink with them. Anytime you consume fluids, you are diluting the THCA concentration that is present in the bladder. This dilution phenomena is only temporary - once the fluids ingested had all been urinated out, the bladder is replenished with fresh THCA-laden urine and thus the donor is right back to square one.

And most of the detox potions instruct the consumer to avoid exercise when using the product. Its actually the lack of exercise is what keeps the THC metabolites stored in the fat cells - not the potion.

In summary, detox drinks are nothing but a big scam to capitalize on the so-called "war on drugs" by preying upon the uninformed and credulous, and taking their hard-earned cash. Cannabis users are victimized enough by the so-called "war on drugs" without these vulturing scam artists swooping down into the mix.