all up and in there's dashboard

A possible misinterpreting of the word "click" from the"fix reply" by Sean Flynn

After opening spam folder locate the messages you accidently marked as spam

open (click) each message one at a time to open and view the message

This is where you should see the "not spam" button. Click on this button after opening each message

The second fix listed by Sean will only move the message back to the inbox folder but will not remove the spam tag you accidently applied