As an independent contractor you can simply let your broker know it's not working and find a new one to move to. Your current broker can't stop you or hold your license hostage; you can leave at any time. If you owe your broker money for things like marketing expenses or past due desk fees, you'll still owe them after you leave but they can't stop you from going.
One important thing to remember, any client you currently have under contract would stay with your broker since a representation agreement like a listing or a buyer representation agreement is generally not between you and the client, it's between your broker and the client. Your broker owns that relationship and this is generally where agents get themselves into trouble by soliciting current clients to come with them in the move.
If this is part of your plan, I highly advise getting really good legal counsel before starting down that path. You could find yourself in a pile of trouble with your current broker, your local board, and maybe even the state regulator. What about commissions? Already booked in the sale of a property that hasn't yet closed on the day you want to leave? Generally, you're entitled to all commissions earned, even if you switch brokers. The real issue can be how or how much your current broker has to pay you for those commissions.
Now, you're going to want to check the independent contractor work agreement that you entered into with your broker when you first started with them. Look for a specific section in that agreement that deals with disbursements of commissions after termination of relationship. Agreements range from the agent keeping all of the expected commission, to an agent keeping almost none of it. Be sure you read the fine print before you make a move.