@Guðjón Viðar Valdimarsson - Welcome to Microsoft Q&A and thanks for reaching out to us.
In order to move resource group to a new subscription, there are some limitations and requirements that you should be aware of. For example, not all resources can be moved, and some resources may require additional steps before they can be moved. Additionally, there may be some dependencies between resources that need to be resolved before the move can be completed.
If you're still unsure about the process, I recommend reviewing the official Azure documentation on moving resources between subscriptions: https://docs.microsoft.com/en-us/azure/azure-resource-manager/management/move-resource-group-and-subscription.
Hope this helps. and please feel free to reach out if you have any further questions.
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