Hello Mahdi,
I think when you build models in parallel, each worker in the parallel pool operates in its own separate workspace and does not inherently share the same current folder or path settings as the client (the main MATLAB session where you initiated the build). This is why relative paths work when building serially (because the single MATLAB session retains the path context) but fail when building in parallel (because the workers start with their default paths, which likely don't include the directories your project relies on).
Initializing workers for build might help you achieving this. Please refer to the following documentation for the same:
However if the issue persists, please create a technical support ticket below:
Cheers!
