Missing components isometrics

Hi,

Some components are missing in the isometrics, although everything is fine in the model.

In some isometric the problem is with pipe, others is with elbows... But that same element goes well in the isometrica if only a smaller part of the line is taken.

Probably is an error in isometric style, any opinion?

Missing component

The only time I have seen this is when the backing sheet used is from an iso that has already passed through isogen and has not been properly purged.