Issue with using RCDC importing geometry from STAAD. When it imports the files, it does not recognize all of the supports or member intersections. When I run RCDC it shows some members as cantilevered, when they should be supported, either by another beam

Have issue with using RCDC importing geometry from STAAD. When it imports the files, it does not recognize all of the supports or member intersections. When I run RCDC it shows some members as cantilevered, when they should be supported, either by another beam or support. How can this be fixed?? All beams are on one level, with no offsets.