SACRAMENTO (CBS13) — As more employers and schools districts require proof of vaccination, problems with the state’s digital vaccine records could prevent some from proving that they’re vaccinated.

An informal CBS13 survey found one out of three respondents were unable to retrieve their digital vaccine record from the state—which may be an indicator that some have no official record of their vaccination at all.

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From concerts to college campuses and California Highway Patrol officers to school teachers, proof of vaccination is quickly becoming a common prerequisite.

With an increase in counterfeit vaccine cards available online, the state’s digital vaccine record is one way to prove yours is legit—and it’s a fallback if you lose your physical card.

You simply enter your name, date of birth, and phone number or email used to make your vaccine appointment, and you’re supposed to get a link to a QR code with your proof of vaccine from the state’s vaccine registry.

Except, for some, it appears there is no record.

CBS13 conducted an informal survey. Out of 50 respondents, 1 out of 3 said they could not access their digital vaccine record from the state. In many cases, they said they’d been fully vaccinated for months.

Half of the respondents who reported missing records said they were vaccinated at pharmacies. Several were vaccinated at pop-up clinics at high schools and county vaccination clinics.

The state says missing digital vaccine records are most often due to typos or contact information that was not submitted by the vaccine provider. “Meaning, while their record is contained in the vaccine progress data system, there can be an issue with matching the contact information that prevents its retrieval, the California Department of Public Health (CDPH) said in an emailed statement.

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CDPH confirmed that was the case for one of the people with missing records from our survey. The state confirmed the pharmacy did not provide his contact information and there was a typo in his last name.

However, CDPH also notes, in some cases, “it’s possible a record was not submitted by the vaccination provider.” In those cases, there may be no official record of the vaccination at all.

“Individuals can check with their vaccine provider or primary care doctor to confirm their information is accurately stored in the statewide registry,” a CDPH representative previously told CBS13. Most providers have access to the California Immunization Registry (CAIR) and can confirm that your record exists.

However, at least one person from our survey found that their health care provider had no record of their vaccine either.

We asked the state if it’s possible that some with missing records are not being counted in the state’s vaccine totals. We also asked what people can do if their vaccine card is challenged and they need immediate proof.

The state didn’t answer our questions directly, but said in a statement: “More than 85% of the people who request their record have it delivered,” and, “We recommend (people who can’t access their digital record) use our Virtual Assistant Tool to start the process of correcting their record.”

Though, the state’s website says that may take 2-3 weeks.

If you were vaccinated at a pharmacy, CDPH says you may be able to ask them for a digital record. “Every CVS and Walmart patient can get a digital version of their vaccine record directly from their pharmacy as these both support the same SMART Health Cards framework that California has implemented,” CDPH added.

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We also asked the state how many people have reported missing digital records, and of those, how many were also missing from the official vaccine registry. We’re still waiting for that data.