Hello @Timo Schöpflin
Azure Free Tier does have several limitations. Unfortunately, but reasonably, you do not have full access to all locations / regions / scales. So therefore it seems to be true, that you can not create the wanted resource in Azure Switzerland. North Region.
To validate, try to create the resource in West Europe and check the result.
Let us know about the validation result and of course if you have any further questions.
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