Have not heard back on 2 issues

Hi There,

I have purchased the pro version. I have been waiting multiple weeks to get a response back from you. When I try and view my feed preview link, I receive the following error message:

This page contains the following errors:

error on line 6 at column 12: Document is empty
Below is a rendering of the page up to the first error.

Also, it says I have en expired token and can’t get this fixed (see below):

Error: invalid_client

The OAuth client was not found.

Request Details
access_type=online
approval_prompt=auto
scope=https://www.googleapis.com/auth/content
response_type=code
redirect_uri=https://whereimfrom.com/wp-admin/edit.php?post_type=product&page=product_woogool
client_id=774-622-1583