Broker won’t lower rate after locking

Is it legal to ditch broker, get loan elsewhere?

DEAR BENNY: I recently purchased a new home. Before I wrote an offer to the seller, I contacted three mortgage brokers to get a loan. After meeting with the brokers ("A," "B," "C"), I chose broker "A" and went through the application process, and was approved for the loan. I signed a lock-in agreement to make sure that the interest rate would not change before closing. In the four weeks before closing day, the stock market was very volatile. My real estate agent told me that mortgage rates were fluctuating up and down. One week before the closing date, market rates for my loan were about 0.5 percent lower than what I had locked in. I asked broker "A" if he would consider lowering the rate in my lock agreement to the current rate. He said that his bank did not allow it. So I called broker "B" and asked if he could lock me in at the current rate. He took my application, processed my paperwork and I signed another ...