it bcs xilinx not support matlab 2021b
you can manually add it in xilinx
\Xilinx\Vivado\YOUR version\data\sysgen\sg_config\ml_supported.xml
<version>
<number>9.11</number>
<name>R2021b</name>
</version>
and using administrator to run vivado
file bar- windows- tcl console
input sg_config in tcl
to set your matlab and apply again
if you already open your vivado. plz close then run in adminitrator agian.
