OpenPlant Modeler pipe run - Extended Locked property doesn`t want to unlock .

Hello,

here is another question: I changed Extended Locked property from unlocked to Locked for one of the pipe runs just to see how it works. I modified the connecting fittings and moved them a little.

so that pie run didnt move (which was good). Once I opened Element information and was trying to change Locked back to Unlocked it started screaming:

And now I cant do anything with it. Any ideas why? How to overwrite?