The check API always returns Internal_error

I'm using Javascript SDK.

dbx.filesUploadSessionStart({ close: close, contents: toUpload }).then((response) => {
                this.entries.push({
                    cursor: {
                        session_id: response.session_id,
                        offset: 0
                    },
                    "commit": {
                        'path': this.path + '/' + toUpload.name,
                        'mode': 'add',
                        'mute': false
                    }
                })
                resolve(response);
});

I run it twice, for exmple. First time close is `false`, the second one is `true`.

And I call `/upload_session/finish_batch`:

dbx.filesUploadSessionFinishBatch({ 'entries': this.entries}).then((response) => {
    ...
});

And I call `check` with `async_job_id`:

dbx.filesCopyBatchCheck({ 'async_job_id': async_job_id })

Frist time it returns `in progress`, second time it returns `Internal_error`