GM insurance

So, a few months back I switched from Progressive auto insurance (15 years) to GM insurance because it saves me $150 a month AND I have way lower deductibles on all 3 vehicles & better coverage. But now that I called to get a quote to add my teen driver (that's it, just a driver) they quoted me another $400 extra a month!!! I've heard of doubling the premium when adding a teen, but not 3 1/2 times as much! Has anyone else had a terrible price increase when adding a teen driver on GM auto insurance?