After some rework on the VIs to eliminate un-needed sequences I noticed a problem with subdiagram label...
As you can see there are at least two residual label floating around... and they cannot be removed in any way (for my limited LabView knowledge).
They cannot be 'selected'
I tried also removing the container sequence but the label persist... I can only change the text inside (of course they are empty).
How can I fix this?