Build issue

I am using Windchill PDMLink Release 12.0 and Datecode with CPS 12.0.2.20 The syncing issue of CAD data with WT part. While using build level option it is throwing an error Build failed: The following parts were not built, because the related CAD Documents are unverified or not regenerated in CAD Tool. Even after regenrating the parts are not build with CAD Data.