N.D. Cent. Code § 16.1-07-10
Upon receipt of an envelope containing the absent voter's ballot, the proper officer immediately shall attach the application of the absent voter and file the ballot with other absentee ballots from the same precinct. If the election official has reason to suspect the signature on the application was made by a different individual than the individual who signed the affidavit on the return ballot envelope, the election official shall attempt to contact the absent voter as soon as practicable to provide an opportunity to validate the signatures. Contact shall first be attempted by phone if the absent voter provided a phone number on the submitted application. If the election official is unable to speak with the absent voter, the election official shall mail a notice informing the absent voter the absentee ballot has been identified as having a signature mismatch and will be rejected if not verified. After submission to the appropriate election officer, a marked absent voter's ballot may not be returned to the voter for any reason other than to complete any missing information required on the affidavit on the back of the return envelope. Before delivering the absentee ballots to the absentee ballot precinct, the proper officer shall package the ballots in a manner so the ballots are sealed securely. The package must be endorsed with the name of the proper voting precinct, the name and official title of the officer, and the words "This package contains an absent voter's ballot and must be opened only according to the processing provisions of section 16.1-07-12." The officer shall keep the package safely in the officer's office until the package is delivered by the officer as provided in this chapter.
N.D.C.C. § 16.1-07-10