External Storage S3 can't upload files

Hello,
we use the AIO installation from the AWS marketplace in our company.
I connected a S3 bucket as an external storage. This works fine so far.

I can delete files preavious of the bucket and can create text file and folders from Nextcloud in the bucket. So read and write permissions are correct.

When I upload files from Nextcloud I always got an error.

“Failed to get fileinfo for /AmazonS3/bucketname/filename”

Log:
Sabre\DAV\Exception: Failed to get fileinfo for /AmazonS3/test1/New-View-Logo.png
OCP\Files\NotFoundException:
OCP\Files\NotFoundException:
Undefined array key mimetype at /var/www/html/lib/private/Files/Cache/Watcher.php#116
Undefined array key storage_mtime at /var/www/html/lib/private/Files/Cache/Watcher.php#134
Aws\S3\Exception\S3Exception: Error executing PutObject on https://s3.eu-central-1.amazonaws.com/XXXXXXXXXXXXXX/test1/New-View-Logo.png; AWS HTTP error: Client error: PUT https://s3.eu-central-1.amazonaws.com/XXXXXXXXXXXXXXX/test1/New-View-Logo.png resulted in a 400 Bad Request response: <?xml version=1.0 encoding=UTF-8?> InvalidStorageClassThe storage class you specified i (truncated…) InvalidStorageClass (client): The storage class you specified is not valid - <?xml version=1.0 encoding=UTF-8?> InvalidStorageClassThe storage class you specified is not validS377C73FBSNFSDX9YWAF/oqP3fGSu8NXXXghYnQoEQhaZcJYBF6o2TI3xu9Ktk02qGf1CeXo8=

Has anybody an idea what’s wrong?

Thanks for reply