Hi Matthias,
Thank you for reaching out and describing the issue you’re experiencing. We’re sorry for the inconvenience caused.
To investigate this issue further and provide you with a solution, could you please share your cPanel access and Joomla admin credentials with us? You can send these details securely via hidden content. This will allow us to troubleshoot the issue directly and identify the root cause. Before sharing this, Please, take your full site backup.
If you have any additional information or steps to reproduce the issue, feel free to include them. We’ll work to resolve this as quickly as possible.
Best regards,