MATTHEWS, N.C. (AP/ WSPA) — Election officials in North Carolina say a mix up in sending the first absentee ballots caused some voters to receive two identical ballots for the November general election.

Mecklenburg County election officials said this week that some ballots intended for voters in Matthews were mislabeled with the wrong names and were shredded before they could be sent. When officials printed new mailing labels to correct the mistake, some voters ended up getting two duplicate ballots.

President Trump tweeted on Thursday about the mix up.

Election Director Michael Dickerson said fewer than 500 voters were affected. He added that it’s unlikely voters could’ve cast two ballots since each mailing label has an individual code making it impossible to vote twice.