Alex Quinonez, the world 200m bronze medalist from Ecuador, was provisionally suspended for whereabouts failures less than a month before the Tokyo Olympics.
Quinonez, 31, had his case referred to a disciplinary tribunal to determine his sanction, if any.
An athlete who has three whereabouts failures in a 12-month span faces a one-to-two-year suspension. Whereabouts failures are typically not being available for a drug test or filing incorrect or insufficient information for drug testers to find an athlete.
Quinonez took third at the 2019 World Championships behind American Noah Lyles and Canadian Andre De Grasse.