hmmm, that's a tough one beata. With my older kids i started by putting them in the cot for the daytime sleeps so they could get used to it before attempting nights- pretty much what your doing. Grace has been in her cot from day one because she hated the bassinette. I think sitting the bassinette in the cot is worth a try, it might just be the new surroundings are unfamilier and she needs to adjust. Sorry i can't help you much!