Hi @louvfx ,
Posable Symmetry works on a single unbroken mesh that must be topologically symmetrical across single axis.
How easily you can recover from this depends on whether the topology has changed at all in your split subtools. If the points along the open mesh borders are still exactly the same and in exactly the same position as when you split them, you can merge your subtools back together with Subtool> Merge with the “Weld” option active. If those points along the borders of each subtool still match exactly, this will fuse them back together.
Otherwise I might recommend restoring an earlier version of the file if one is available. All the other options for fusing subtools together will result in a topology change. I can’t think of a way off the top of my head to restore topological symmetry for a mesh that has already been posed in an asymmetrical fashion. You would need to restore the model to mirror symmetry and begin the posing process over again. This could be done with Geometry> Modify Topology> Mirror and Weld.
