Hello @Olivier ,
Thanks for reaching out.
Could you please confirm, how did you remove subscription? Do you mean "Cancel Subscription" or "Delete Subscription" ? If you cancel your subscription with Pay-As-You-Go rates , you can reactivate it in the Azure portal.
Make sure, you have require permissions (Service administrator or subscription owner) to reactivate a subscription. An account administrator without the service administrator or subscription owner role can’t activate/cancel an Azure subscription. However, an account administrator can make themself the service administrator and then they can cancel a subscription. For more information, see Change the Service Administrator.
More Information, refer who can active/cancel a subscription
If your subscription isn't a subscription with Pay-As-You-Go rates, contact support within 90 days of cancellation to reactivate your subscription.
Hope this helps.
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