WASHINGTON - Some companies that sell food and agricultural products to Cuba are reporting that payments are not being credited to their bank accounts in the United States, according to a representative of a group that tracks business between the two countries. John Kavulich, president of the U.S.-Cuba Trade and Economic Council Inc., said Tuesday that fewer than half a dozen companies have contacted his organization recently about such problems. He said banks have confirmed receipt of payments from Cuba but have not credited the accounts of exporters on instructions from the U.S. government. A spokeswoman for the Treasury Department...