Hi @Christian Schmittel,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We sincerely apologize for the inconvenience caused.
If your Azure subscription reaches its spending limit, servers may be automatically disabled. As you mentioned, you have increased your spending limit, and while all other VMs were enabled, the server in question remains disabled.
Kindly verify whether the subscription is enabled or disabled. If it is disabled, please check if you can open a support ticket. If you are able to do so, kindly file a support ticket for further investigation and share the SR# with us. If you do not have a support plan, please let us know here.
I hope this information helps. Please do let us know if you have any further queries.
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