Hello @Johannes Keim , Thanks for using Microsoft Q&A Platform.
Are you using the OpenAI studio or Azzure AI studio?
Try the same operation on the OpenAI studio. Select your subscription and resource correctly -
Try and deploy the model here. Check the list of available models from https://learn.microsoft.com/en-us/azure/ai-services/openai/concepts/models#standard-deployment-model-availability
If this works smoothly, change the scope on the AI studio to your subscription and resource and continue using the studio. You need to set the scope as resource instead of resource group.
Alternatively, can you make sure the resource group exists, and this resource is a part of it. What level of access do you have over the resource Group?
Let me know if this works