error using export function 

I'm getting this error while using the exportAssistant function:

```[ERR_INVALID_ARG_TYPE]: The "data" argument must be of type string or an instance of Buffer, TypedArray, or DataView. Received an instance of Object```

and then

```TypeError [ERR_INVALID_ARG_TYPE]: The "path" argument must be of type string. Received an instance of NodeError```