Hi @Gioany F
Could you please share us with the messages that let you upgrade OneDrive or the reminder that you cannot use personal vault?
How much storage space does your OneDrive have? Besides, how much space is available now?
Please note you need to upgrade to a Microsoft 365 Personal or Family subscription to store more than 3 files in Personal Vault.
OneDrive 100 GB plans and Basic 5 GB free accounts can store a maximum of 3 files in Personal Vault
For more, please check out: Find out more about Personal Vault
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