@Dewa Tsukasa Greetings from Microsoft!
It seems like you have followed the correct steps to ensure that the tags are applied to the resource groups and that you are viewing the Cost Analysis as a user with the "Tag Contributor" role assigned. However, there are a few additional things to consider when troubleshooting why tags are not appearing in the Cost Analysis.
First, make sure that the tags were applied directly to the resources and not just to the resource group. Resource tags are only supported for resources deployed to resource groups, and tags must be applied directly to resources and aren't implicitly inherited from the parent resource group.
Second, check if the tags were applied more than 24 hours ago. Resource tags are only included in usage data while the tag is applied, and tags aren't applied to historical data. Resource tags are only available in Cost Management after the data is refreshed.
Third, ensure that the resources are active/running and producing usage records. For example, when a VM is deallocated, it will not produce usage records and therefore will not show up in the Cost Analysis.
If you have confirmed that all of these conditions are met and the tags are still not appearing in the Cost Analysis, it is possible that there may be a delay in the data being processed. In this case, I would recommend waiting a little longer and checking again later.
If these steps do not resolve the issue, you might need to reach out to Cost Management support team by raising a support request for further assistance.
FYI: Cost Management support is included in the Basic Support Plan without any charge.
https://azure.microsoft.com/en-us/support/plans/
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