The California Department of Health is notifying about 6,300 people to tell them they received a less-than-recommended dose of the COVID-19 vaccine, according to multiple reports.

Over the course of two days at the Oakland Coliseum, thousands were underdosed, reportedly because of the kind of syringe that was being used. Meaning, some of the vaccine may have remained in the syringe when a vaccine was administered.

Reports of the underdosing came to light last week when staff working at the Coliseum came forward with their story.

Health officials say people who may have received less than the full dose do not need to do anything different, and should make sure they get the second vaccine dose.

"While the recommended dose of the Pfizer COVID-19 vaccine is 0.3 ml, the CDC has determined that any dosage of 0.15 ml or larger is safe and does not require the dose to be repeated to protect people against COVID-19," Ali Bay, a spokesperson for the Department of Public Health, wrote in an email to the media.

"In this instance, some individuals may have received a dose of 0.22 ml, which is well within the range outlined by the CDC."

State officials say once staff at the Coliseum realized the syringes weren’t giving the full dose, they figured out a solution and correct doses were given.