* In the military: A major is a field-grade officer. Above a major are lieutenant colonel, colonel, and then higher ranks.
* In a hotel or restaurant: "Major" isn't a standard term for a position. The structure varies widely, but roles above a position equivalent to a major might include a general manager, regional manager, or corporate executive.
* In other service industries: Similar to the hotel/restaurant example, there's no standard "major" role. The structure is entirely dependent on the specific organization. You'd need to provide more context.
To answer your question properly, please clarify which "service" you're referring to.