Problems with BRepAlgoAPI_Fuse

Hello,

I have a problem with BRepAlgoAPI_Fuse. I have about 50 Solids which I want to fuse, but every Time on Solid 19 I got this error:

"BOPTools_PaveFiller DoSDEdges - can not find SplitIndex"

Does anyone knows what this message could mean? I try to heal each Solid before fusing with

ShapeFix_Shape sfs (fusedSegments);
sfs.Perform();
fusedSegments = sfs.Shape();

but it changed nothing.
Anyone has a Idea about this?

Thanks!
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