backup of changes not possible

Hello,
I have had several problems with your application for several days:

1 – when I make changes in the general settings for images and the robots.txt file, I can’t save the changes. Indeed, when I click on “save” I land on a page 404. As a result, my modifications are not taken into account.

2- I have the same problem when I try to connect my Google Search Console account and I click on the “save” button I land on a 404 page. This makes it impossible for me to connect to my Google Search Console account.

3- When I try to connect to my Google analytics account, I can only select the information in the “account” field. But I can’t select anything in the “Property” and “view” fields. Therefore, I can’t fill in “a property”, nor a “view”.
And when I click on “save”, a message appears “There are unsved changes”.
So I can’t save

Can you help me?

Thank you in advance.

Have a nice day.

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