Thank you very much for your answer and attention. I thought the tertiary submenu was not visible. But there were very few visible icons. But clicking it works. When it comes to it it doesn’t work(hover). This is not important either.
The site is still in testing phase.
https://drive.google.com/file/d/1mcSk0_em8IlGQvqZkPK_wPJZf28M8ku3/view?usp=sharing