Spring guns will destroy a normal scope. Assumably, Gamo is including an airgun specific scope. With the scope adjustment caps at 90 degrees and the top cap pointed straight up, the crosshairs should be level. If they aren't, the scope is bad and must be replaced. There is no other adjustment that will resolve this. The 'cage' the crosshairs are mounted in is moving inside the scope. It can happen with just about any scope but is pretty common in cheap scopes. Call Gamo and see if they will replace it or look around for a good airgun specific scope. If it doesn't say it's ok for spring gun use you'll be wasting your money.