how to ensure user Authenticated via MSAL is same as user logged into the iframe?

Question

I am using MSAL to authenticate a Microsoft account using Microsoft Entra Id and retrieve an authentication token for the logged-in user. After saving a file to the user's OneDrive using that token, I display the file in an iframe within my application. However, the iframe seems to be using the global user context instead of the MSAL authenticated user. How can I ensure that the iframe uses the same logged-in user from MSAL for authentication? Or is it something that is not possible? Also if there is any other way as well to achieve something like this?