That is something you can do when buying a toaster at Aldi, but when it comes to a contract regarding houses, one should not rely on belief or "it seemed logical to me."
Thank you very much for your note, but the question does not concern "What would have been correct"...
OK, it has been exceeded, you want to have an object standing there.
I am really annoyed that we have not received any response to our inquiries for 2 months. The house was actually supposed to be standing by the end of the year.
That is not correct. Oral side agreements rarely have enforceable significance and are often expressly excluded in the contract, What is your goal and what is the goal of your contracting party?
I had the feeling over the past few weeks that they simply do not want to disclose their positions and insisted that we eventually say "enough is enough".
Ask the license partner what they actually want. There might be goal congruence. If not - what would be the consequences of termination on your part? Is there an end to the contract?