I had worked in a lab for my master's thesis. But I could not complete a course from the previous semester so I could not register for defense at X University. This university asked me to transfer my credits. Now I am trying to transfer my credits at Y University. Their response is positive and they asked if my thesis was completed or not. If yes, I don't have to do it again. If not, maybe I have to repeat. My question is what should I write them? I have worked and wrote the introduction and method. Then I left the lab and could not continue. If I want to complete my writing, then I have to contact my thesis supervisor again? Is it possible that he will cooperate?
1) you have to say your thesis is not complete.
2) you need to contact your thesis supervisor for a plan of action to finish.
Of course if you decide not to finish the thesis at your old institution, then the new one may still accept you, while expecting you to complete perhaps with them. But they have to know whare you are - see 1...