I have escalated this ticket to our 2nd tier of support, where our specialists will take a deeper look at this issue and will try to isolate its cause. I will keep you updated on the evolution of this ticket.
Thank you very much for your patience and understanding!
Our 2nd-tier specialists found that the cause of the issue is some incorrect entries in the database. Do you authorize our 2nd-tier specialists to install a database manager plugin to fix the problem?
The original issue for this ticket is about cloning the content to the secondary language, and you have added three more problems. I kindly ask that you stay focused on the original problem, and then we can continue working on the others. Otherwise, we will not complete this ticket and will mark the original issue as resolved.