The Index registers IISP0A and IISP1A should be loaded with the address of the variable instead of its value. But in your case , I think you have put the value of the variable instead of its address .
I have attached a working code in which SPORT0 is the transmitter and Sport1 is the RX , the DMA count is 1 and the Index registers are loaded with the address of the variable to be transmitted and the address of the variable where the data has to be received.
Please let me know if you have further doubts.
Thank you for your answer. But my problem is resolved otherwise. I used SPORT2 for TX instead SPORT0 and now all right. And I think that the problem was with the priorities DMA (SPORT0 and SPORT1 have equal priority).