Married status to single ID

Hello, could you please advise po what is the best thing to do. Yung mother ko po, her IDs - National ID, Voter's Certification, gamit po nya yung apelyido ng tatay ko. But Wala po Silang record ng kanilang marriage, walang ma present na marriage certificate while trying to apply for her passport. Now po, pwede po bang ipachange yung name nya to her maiden name, using the CENOMAR or what documents could you advise po?

Thank you.