Teachers haven't recieved rec forms

<p>Hi,
I'm using the common applications online school forms. I invited the teachers last month, and my common app profile shows the teachers have not started. I contacted one of the teachers and she said she did not receive the form so, I re-invited her. How long does it take for them to get the forms? Has this happened to anyone else?
Thanks.</p>

<p>The email is sent by the common app website to your recommenders immediately when you invite them and add him/her to your schools. Double check the email address you entered and be sure to tell them to look in their spam or junk mail boxes for the message.</p>