Unable to create new attributes in Akeneo | Error: This code is already used

I have a fresh installed Akeneo CE Server. Unfortunately I'm not able to create new attributes. At the moment there is just one attribute "SKU", which was created during the installation process.

As soon as I try to create a new attribute, I get the error message "This code is already used". Please see the attached screenshots.

Akeneo Version: CE 7.0.26
Server: Debian Server 11 (Bullseye)
PHP: 8.1.23
MySql: PHP 8.0.34
NodeJS: 18.17.1
Yarn: 1.22.19

Things which I already tried:

• I tried different names and different attribute types.
• I also installed different Akeneo versions from 7.0 to 7.0.26 / Always the same error
• There are no related errors on the server logfile
• I didn't get any javascript errors on the browser console

Any ideas on how to solve the problem?

Error attribute overview

We were able to solve the problem by ourselves in the meantime. Incorrect rewrite rules in the vhost configuration were the problem.