Can't change Website title

My website title is still "Contao Open Source CMS." I can go into the settings screen to try and change it, but I keep getting an error that a required field is empty.

When I first go into the settings screen, the following fields are empty.
E-mail address of the system administrator*
Encryption key*

I can enter my email address and a 15 digit key and press save. When I press save, the page refreshes (or I think it does, and the window opens halfway down the page (like if you refreshed a long web page when you were viewing content in the middle of the page). After pressing save, the email address and encryption key fields are blank again.

If I edit the website title, email address, and encryption key fields all at the same time, the same thing happens.

Has anybody had this problem before?

A quick note....

I'm using Contao Open Source CMS 2.9.4

First run contao-check.php for your version to test your server and the core files, then if everythimg is ok, run your install tool again.

That is your backend title, which you can change in settings. The website title you can change in the website root page, by changing the pagetitle (which can be different from the page name).