@Annarose.Peterson - hey hey. So when I have run into unpredictable SAML types of Interactions in the past? I would reach out to two teams, sometimes it was on the product side and sometimes on the SSO itself. 

SSOs can have a lot of little things get funky with them. Many of them support a user log or console mode so that a developer or user support can see what’s going on with the saml insertion. For example unexpected or missing data coming along from your IDP (identity provider) can throw it for a loop.

I hope some of this helps…

This could also be your firewall blacking something. It might be worth asking Docbo where your server is hosted and asking for the IP Address range so you can ensure your IT Department white list them. This is the list I give to all of my clients to get them to whitelist these: (your IP addresses may be different - however check the one in bold is whitelisted)