A campaign staff member for presidential candidate Tom Steyer resigned on Monday after downloading Kamala Harris' campaign data.

Dwane Sims, who previously worked for the South Carolina Democratic Party, downloaded volunteer data from Harris' campaign, according to The Post and Courier.

According to NBC News, the state party restricted the Steyer's campaign access to a system over a miscommunication of payment.

When the access was reinstated, a glitch in the system restored Sims' profile at a level he previously had while working for the South Carolina Democratic Party.

Sims was granted access at a higher level than what he should have as a campaign staffer, according to NBC News. Sims had retained a separate user account using a personal email address, allowing him access to the data.

Sims allegedly started downloading Harris' data with the impression he was downloading information for the Steyer campaign. 

"Within minutes of realizing this, Mr. Sims called the South Carolina Democratic Party to let them know of their oversight," Benjamin Gerdes, Steyer's national press secretary, told NBC News. "He acted quickly to alert the appropriate people to rectify the matter, and the access was turned off by the party authorities."

The former Steyer campaign staff member's account was disabled by the state party and the Democratic National Convention. He was sent a cease-and-desist letter, demanding he deletes the downloaded information on his laptop, according to The Hill.

According to the Steyer campaign, Sims deleted the data and had his computer swiped clean by an internal IT department.

"All data downloaded by this individual was destroyed and was not provided to any third parties. It is critical that the Steyer campaign take immediate action regarding their employee," SCDP Charman Trav Robertson said in a statement. "This user account did not have access to data from any other presidential campaign."

The Harris campaign didn't release a statement on the incident, however communications director Lily Adams commented on a retweet of the story. 

An internal investigation was completed before Sims' resignation was announced.

Campaign-DataDwane-SimsKamala HarrisTom Steyer