Hi @jawaher almutairi ,
Welcome to our forum!
Are you using Outlook.com or Outlook desktop client?
If you are using Outlook.com, as I know, email is automatically deleted from the Junk Email folder after 10 days, as mentioned in this official documents.
If you have configured other types of accounts in the outlook client, such as Microsoft 365 account, it's suggested that you could right click Junk Email folder>Properties>click Policy tab, and then you will see the specific retention time in the JunkMail retention policy set by your organization.
Hope to help you!
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