Error when Merging PPTX by PHP via Slides Cloud API

Here my code

 $slidesApi = self::getCloudApi();
        $fileName = "file_2.pptx";
        $fileName2 = "file_3.pptx";

        $inputFolder = storage_path('app/public/');

        // Upload original documents to storage
        $fileStream = fopen($inputFolder . $fileName, 'r');
        $slidesApi->uploadFile($fileName,  $fileStream, '24h store');

        $fileStream2 = fopen($inputFolder . $fileName2, 'r');
        $slidesApi->uploadFile($fileName2,  $fileStream2, '24h store');

        $mergeList = new PresentationsMergeRequest();
        $mergeList->setPresentationPaths(array($fileName, $fileName2));

       $res = $slidesApi->merge("test_merge.pptx", $mergeList, null, null, '24h store');

I use storage of Aspose but the error is

Error: Merge. Exception: Error processing presentation file_2.pptx: AmazonS3 Storage exception: The specified key does not exist. Bucket ‘aspose.cloud-filestorage-prod’

Does I miss anything?

@taihojavac,
Thank you for contacting support.

Unfortunately, I was unable to reproduce the error you described. What method is throwing this error (uploadFile or merge)? It would be great if you could share the presentations: file_2.pptx, file_3.pptx, test_merge.pptx.