If it went south on you after simply being "jarred" while placing it in your SUV then it has a problem. A scope that delicate is pretty much useless.
The "tapping" on the tube is for scopes that refuse to move when adjusted due to the adjustment mechanism sticking (like it's gummed up). The tapping helps to get the internals to move. Even then, this would indicate to me that the scope needs medical attention.
Perhaps you could just replace it...send it to be repaired...and sell it when it's fixed (or keep it as a back-up). If they refuse to fix it under warranty then you already have a scope and that one can be trashed or fixed on your dime if it's cheap enough.
IDPA Member A00640
Founding Charter Member - Middle Tennessee Shooter's Club