@Marco Rozo Thanks for posting your query on Microsoft Q&A.
In addition to the suggestions shared by Shiva above, you can also try to
- delete the Classic Storage Account from the Storage Explorer or
- migrate Classic Storage to ARM and delete it there.
I hope this helps! Let me know in the comments if you have further questions. Comment is the fastest way to reach the experts for any questions or help you need.
Please don’t forget to Accept Answer and hit Yes for "was this answer helpful" wherever the information provided helps you, this can be beneficial to other community members for remediation for similar issues.