problems with update to 2.9

I did the update to version 2.9 of guardian and the website since then is not visualized properly, the font is different, the menu appears different. The only way to see it as it should be is to be logged-in as wp admin. I have guardian on 4 websites, and only in the one I did the update I’m having this problem. This is the website with 2.9: https://www.ayahuascarebirth.org/it/

In this one, where I have not done the update, the homepage is the same even I’m logged-in or not: https://www.ayahuascarebirth.org/

I hope to be able to solve this problem, the website now is very bad…

Thank you!