A voice assistant does not hold a private file on your company. It typically draws on, map data, your website, and reviews that already exist, so voice work is mostly the quality of those public sources. We do not claim to know which source a given assistant favors on a given day, and nobody outside those companies does. What we can control is whether every source says the same true thing.
Apple is a good example of how directly a business can shape a listing. On its Apple Business Connect page, Apple tells owners to "Claim your location on Maps so millions of customers can connect with your business" and says you can "Control how your business appears with your logo, hours, images, and key details." If your Apple Maps hours are wrong, a person using that map is told wrong hours.
Google works the same way on its side. Its documentation says "Local results are mainly based on relevance, distance, and popularity," and "Distance refers to how far each business is from the customer who’s searching." Distance is fixed by where the customer stands, so completeness and accuracy are the parts you can control. The Google local ranking guide lays out those factors.