Thank you for reaching us!
I am glad to hear that your issue is fixed. Based on your explanation, it seems that there may have been an issue with the registration of your free subscription. If your free subscription may have been filed under your previous employer's account Azure free subscription might not accessible after removing association with previous organization. Also, it might be the below reasons.
Previously if You have already used up your free trial subscription and it might has expired, or you have switched to a different Azure directory that does not have your free subscription.
I hope this Answer helps! If you have any further questions, please feel free to ask.
Reference: https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/subscription-disabled
Thanks,
Akhilesh.
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