SAN FRANCISCO (CBS SF) — Two winners of California’s “Vax To Win” Lottery ignored several attempts by state officials to reach them, thereby foregoing their chances to collect $50,000 awards, state officials announced Thursday.

“The two originally drawn were notified in very explicit terms of yesterday’s deadline by which they would have forfeited their cash prize,” Sami Gallegos, press secretary for the California COVID-19 Vaccine Task Force.

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The prizes are part of the largest COVID-19 vaccine incentive program in the United States. California’s COVID-19 vaccination rate was still less than 50% as of Thursday.

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The cash prizes will now be given to two alternates — one from Sacramento County and one from Monterey County. Only the winner in Monterey has responded to the state’s messages.

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Gov. Gavin Newsom drew the first round of winners from 21 million participants last Friday.