My emails are missing.

I tried to restore deleted emails (that were somehow deleted yesterday morning, along with the entire POP folder) but they are not getting restored. In reading a similar post, it said that recently deleted emails can be recovered. Are my emails gone now? Many of them were flagged, because I had an action item related to those emails to follow up.

Please advise as to how I can restore the emails that were deleted yesterday or how to restore my email account to a previous day/time or some other workaround.