I’m unable to release the dragon on Level 3030

No there is no glitch and never has been a glitch. It is just difficult to pass this level so some players have thought it must be a glitch. You have to hit the magic mixer at total of five times (mostly with striped candies from below) for it to explode and release the dragon. Each time you hit it one of the four little screws in the corners disappears. Once all the screws are gone you need to give it one more hit.

To illustrate I have used lollipop hammers to release the dragon, watch the screws in the corners disappear:

After a fourth lollipop hammer all four screws are gone. For the last hit I used a striped candy from my inventory, releasing the dragon.

Of course to pass this level you need to use a different strategy, it was just to illustrate there is no glitch in the level.

You have to hit the mixer five times. Each time you hit it one of the screws in the corner comes out. When all the screws are gone the mixer takes one more hit and it will explode and release the dragon.