Just to make sure this is clear: MATLAB Builder JA is a separate product, used with at least MATLAB and MATLAB Compiler.
I suppose you verified using the VER command that the MATLAB Builder JA is not installed. The next step is to go to the administrator of the license. Often, a product is available in larger licenses, but not installed for each user. Also the rest should be done (or explained) by the administrator.
Assuming your company or university has no license of this product, please get in touch with a Mathworks sales representative: