Using 1 SSO provider, person A logs in, then logs out of our app, then person B is logged in as person A since person A's stilled logged into the SSO

Question

I'm using Component Space in a C# API, which interfaces with an angular app.

Everything is working beautifully in most circumstances. However, when I log in person A, and then log out of the application (but they remain logged in with the SSO provider), then try to log in person B using the same SSO provider, I'm not given the opportunity to log in with SSO because person A is still logged in via SSO. Then my app recognizes this and provides an error and nobody is logged in. This is not ideal for us; we would prefer for person B to be logged in as desired.

We have tried sending in the Requested username, but it is totally ignored (in this case by PingOne) if a user is already logged in on their end. With Active Directory we get an error when trying to send that information.

This is how we send in the requested username:

SAMLServiceProvider.InitiateSSO(response, relay, config.entityId, new SSOOptions
{
    RequestedUserName = username
});

We would have expected that we would get an opportunity to switch to the provided user.