Here's what current US Centers for Disease Control and Prevention guidelines say on possible reinfection:
"Data to date show that a person who has had and recovered from COVID-19 may have low levels of virus in their bodies for up to 3 months after diagnosis. This means that if the person who has recovered from COVID-19 is retested within 3 months of initial infection, they may continue to have a positive test result, even though they are not spreading COVID-19.There are no confirmed reports to date of a person being reinfected with COVID-19 within 3 months of initial infection. However, additional research is ongoing. Therefore, if a person who has recovered from COVID-19 has new symptoms of COVID-19, the person may need an evaluation for reinfection, especially if the person has had close contact with someone infected with COVID-19. The person should isolate and contact a healthcare provider to be evaluated for other causes of their symptoms, and possibly retested."