vst transit - problem on locked track as owner

Hello all
I am happy owner of cubase 10,5 and i was going to share a project with a guitarist through vst transit. I experienced a problem:

I wanted to share an instrument track, with an instrument that i was sure my friend did not have. So i freezed the VSTintrument, hoping that the generated audio track on the intrument track would have reached the cubase of my guitarist.

It didn’t work, but this is not the point. the guitarist touched that track, don’t know exactly what he did, but after that, i synced again the project, and from that moment my instrument track was locked! there was no way to unlock it, even if i am the owner.
I tried then to duplicate the track, then send it to my friend without unfreezing, but still that duplicated track after the sync in VST transit, appeared locked too. no way to unlock it.

very strange. any idea about this ? My project has still those 2 locked track and i could only disable them, cause i also cannot delete them…
Thanks a lot for help

haven’t heard this before. Especially when you copy a track it becomes yours. Did you change anything in between, like changing your user account?