There may be an angle using the Spanish Consumer Law and mortgages but I am obvioulsy not sure of your financial status or even if you were planning a mortgage
Under the law if a buyer can prove that, due to a change in their financial status, that they are unable to get a mortgage and can prove 3 refusals, then they can re-cliam all of the money paid
Even if you were not planning to mortgage you could of course decide on a mortgage now