I have completed the lessons offered and there are no new ones presented. It is a glitch in the system.
You posted this in French, but you're currently active in your Spanish course, so I'm not sure which course you're talking about.
Here's a Help article that might explain things: https://support.duolingo.com/hc/en-us/articles/204777904-I-m-stuck-why-can-t-I-open-the-next-skill-
Your next lesson in Spanish is Lesson 1 in the "Household" skill set.