You didn't indicate the age of the scooter. Is it under warranty ?
If it blows the main fuse even with the ignition switch off, then there is a shorted wire at or before the ignition switch.
Or the fusebox or ignition switch may be shorted.
If you have an electrical skills, you can start to find the problem.
Get a small 12 volt light bulb and solder wires to it and attach the wires in place of the fuse that keep blowing.
If you can't do that, then buy a 12 volt marker light and attach the wires in place of that fuse.
The idea is that the light will glow if there is a short further away. Then you can wiggle the wires between the fuse and the ignition switch to see if the light goes out (short becomes unshorted). That can help identify the approximate location of the short.
Once you find the general location of the short, you may be able to insulate the wire or replace the faulty component.
Using a light bulb in place of the fuse allows you to not have to keep replacing a blown fuse.
Ypu may need to buy a multimeter to isolate the problem.
And you may have to charge the battery if you spend a lot of time with the light burning.
I hope this helps.