You'll have to dig deeper for more specific information regarding the rate of false positive results, but perhaps that is what has happened in your case. Here's an excerpt from the mayo clinic :
Risks
As with any screening test, an HPV test carries the risk of false-positive or false-negative results.
False-positive. A false-positive test result indicates that you have a high-risk type of HPV when you really don't. A false-positive result could lead to an unnecessary follow-up procedure, such as colposcopy or biopsy, and undue anxiety over the test results.
False-negative. A false-negative test result means you really do have an HPV infection, but the test indicates that you don't. This might cause a delay in appropriate follow-up tests or procedures