Hi @Franziska 🦊 ,
Welcome to Q&A forum!
As far as I know, OneDrive Standalone is a plan for purchasing additional storage space for OneDrive. For more information, please refer to: Compare OneDrive cloud storage pricing and plans.
Besides, please note that we are focused on general issues about OneDrive client, and the issues related to billing are not support in Q&A forum currently. It is recommended that you go to the following page to seek more professional support and help.
Microsoft Store & billing help
Thanks for you understanding.
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