回复：问题是我的老房子卖不掉，再加上新的，房子贷款是通不过的

Then you should be able to get your 新房定金 back. Read your contract again, there should be a cluse that you need to be able to get a loan to buy the new house. If you can not get the loan without sell your old house then you will be able to get the 新房定金, otherwise your agent is too bad.