Hi @Magaly-Et-Jean-Christophe0
If I understand your issue correctly, it's similar to something that frequently happens to me. Restrictions that I have put in place, prevent me from opening dates on the calendar and I get a message that says the nights remain blocked because of some restricted check-in or check-out issue.
From what I understand @Joan2709 is saying that this ideally shouldn't be so and that the calendar ought to allow us to just unblock dates. I didn't realise that, I just accepted that I had to delete all my restrictions near those dates, unblock the dates, and then set the restrictions again. It works for me, but it can be cumbersome.