Power BI Embedded Row Level Security, Couldn't load data for this visual 401 error

Hello!

Using the Sample at:

https://docs.microsoft.com/en-us/azure/power-bi-embedded/power-bi-embedded-get-started-sample

And following the article at:

https://docs.microsoft.com/en-us/azure/power-bi-embedded/power-bi-embedded-rls

I am unable to get RLS working on an embedded report. The error received is as below:

The Report works fine with RLS removed, but allowing user based RLS will be cricual to our business.

The Sample Embed token has been changed to:

IEnumerable<string> UserRoles = new List<string>() {"provider"};
var embedToken = PowerBIToken.CreateReportEmbedToken(this.workspaceCollection, this.workspaceId, report.Id, "10005", UserRoles);

The Role is called "provider", and has the following filter:

[provider_ID_INT] = USERNAME() || [provider_ID_INT] = "-1"

When testing this in power bi desktop with "10005" entered into other user, the RLS works perfectly.

The Report contains 3 data sets, one with a list of distinct providers, which links to two data tables based on a ID. 

The list of distinct providers has the Role applied to it.

The data sets are imported, direct query is not used.

I have seen similar forum posts but none with a solution.

Has anyone found an answer to this, 

Or might anyone know what i am doing wrong.

Thank You!