Mails disappeared from Inbox subfolders

Mails disappeared from Inbox subfolders

Since yesterday all mails disappeared from my inbox subfolders. What is happening here?
Only mails in Inbox folder are still there.
Please fix this as I have very important data in those mails.
Is this a known problem? Never happened to me before.

Here is a screenshoot...

Zoho mail - disappeared mails in subfolders_2