Positive Then Negative Ffn Test Has Anyone Ever Had A Negative Fetal Fibronectin Test After Having A Positive One?

Has anyone ever had a negative fetal fibronectin test after having a positive one? - positive then negative ffn test

at 25 weeks and found a positive ffn test last week. Til the rest on the bed, next Thursday, then they're going to try again. Is there a way to negative returns? Ive had to develop two steroid injections for the baby's lungs, and vaccines to stop the labor.