Your comments

Thanks, Lori. Strange, but the guys are on it. Someone will reply very soon. - SauL
Thanks for that. We had tested everything - but the Smart Inbox. I got the same thing as you and put the guys on to it, Charlie.  I'm going to go out on a limb and predict that they fix this by the end of the week. - SauL
Can you please check whether you have selected Person / Company radio button. This may prevent the settings from being saved. 

Best

Michal
Have you checked oAuth documentation: http://oauth.net/ and our sample code: https://bitbucket.org/ritetag/ritetag-api/overview?