could'nt load the data for this visual - power bi embedded for customers

Hi Karola 

Here you are using app owns data to embed your report to your customer. You customers don't need to have access to Power BI. They will access your embedded report in portal by embedded token you assigned to them.

Each token has its lifetime, so I think your issue should be caused by embedded token expiration.

This is the workloads that how your customer gets embedded token.

For reference: Embed for your customers

Based on my research, we can try to use the token lifetime policy and Assign policy to a service principal to configure the expiretime up to 24 hours, please refer to this document and thread: 

Configurable token lifetimes in the Microsoft identity platform (preview)

Access token setting expiration times

You can also keep the default expire time and generate a new token before expire to update. when generate an embedded token, it will return the expire time, then you can generate a new token before the expire time, please refer to the example code with javascript

https://github.com/microsoft/PowerBI-JavaScript/wiki/Update-Embed-Token

https://github.com/microsoft/PowerBI-JavaScript/wiki/Refresh-token-using-JavaScript-SDK-example

we did not find sample code by RESTful, but the logic should be similar.

Update:

following policy make the expire time up to 2 hours (token refreshed when 04:55 UTC+0)

$policy = New-AzureADPolicy -Definition @('{"TokenLifetimePolicy":{"Version":1,"AccessTokenLifetime":"02:00:00","MaxAgeSessionSingleFactor":"02:00:00"}}') -DisplayName "ApiDefaultPolicyScenario" -IsOrganizationDefault $false -Type "TokenLifetimePolicy"

Best Regards,
Rico Zhou

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