Here is the only article that I have found
https://www.aol.com/ballot-error-shuts-down-montana-021700946.html
https://dailyinterlake.com/news/2024/sep/20/ballot-error-shuts-down-montana-online-absentee-voting-system/
When Max Himsl opened his electronic ballot on Friday, he was dismayed to see a candidate missing from the list of options.
Voting absentee electronically while living abroad, Himsl saw that under the options for president, only Republican Donald Trump and Independent Robert F. Kennedy Jr. were listed. Missing was Democrat Kamala Harris.
Im upset my democratic process was interrupted, he said.
Election officials were notified of the error shortly after the Electronic Absentee System that allows certain voters to cast their ballot electronically went live on Friday at 8 a.m., according to the Montana Secretary of States Office which reported that the error was isolated to the online system.
Our team and the vendor quickly investigated and found that only a few voters may have been impacted, the Secretary of States Office said through email. As a precaution, the Electronic Absentee System has been taken offline until troubleshooting is completed.
The system was expected to be available to eligible voters later Friday, including those few voters who may have been impacted, the office said. ......
"This is very concerning to me," said Himsl, who reported the issue to the Flathead County Election Department on Friday morning. Soon after he received an email notifying him that the Montana Secretary of State's office was aware of and working to correct the error.