SysGen part of the design can be synthesized. But, it's not possible to synthesize the MATLAB block by SysGen tool.
Can you share the screenshot of the issue/error.
/ 7\7 Meher Krishna Patel, PhD
\ \ Senior Product Application Engineer, Xilinx
/ /
\_\/\7 It is not so much that you are within the cosmos as that the cosmos is within you...