Hi @NB
Thanks for reaching out to Microsoft Q & A Forum's .
Speaking of your question , Yes when ever you purchase an azure account only one subscription is created .
If you are having 3 subscriptions listed on your azure portal/CLI that you are not aware of , Please create a Support ticket to our billing team using the following and they will help you further after validating your account :
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/create-subscription
Hope this will help you in this situation .
Thanks,
Pradeep
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