Two days ago, I have been opening the Blocks section, but it does not work. That is, a white page appears and the Blocks section does not open in my project.
Hi @hafez12345hasand2j , welcome to Thunkable! 
Could you please share the specific project URL with us so we can investigate it further?
You could copy it from the top of your browser.
This way we could find the best solution for you.