InvalidRequest when getting download url from S3

here is the code, to add, the only update I remember making on the bucket was making it public, I have now reverted that setting but the issue persists. This same code worked in the past. public String getPresignedDownloadUrl(String filePath)throws Exception{

    //the filePath here represents the filename. this is how I saved the file
    try {

        // Create a new instance of the AWS SDK S3 client
        AmazonS3 s3Client = AmazonS3ClientBuilder.standard().build();

        // Generate a presigned URL for downloading the S3 object with response headers
        Date expiration = new Date(System.currentTimeMillis() + 3600000);
        ResponseHeaderOverrides responseHeaders = new ResponseHeaderOverrides()
                .withContentDisposition("attachment;filename=" + filePath);

        GeneratePresignedUrlRequest generatePresignedUrlRequest = new GeneratePresignedUrlRequest(bucketName,  filePath)
                .withMethod(HttpMethod.GET)
                .withExpiration(expiration)
                .withResponseHeaders(responseHeaders);

        URL url = s3Client.generatePresignedUrl(generatePresignedUrlRequest);

        // Use the generated URL to download the S3 object
        return url.toString();
    }
    catch (Exception ex)
    {
        throw new Exception(ex);
    }
}