Hello. Thank you for contacting the Toolset support.
Can you please share admin access details and tell me the link from where I can buy/purchase the camp as well as what Toolset form you are using to send the email notification.
*** Please make a FULL BACKUP of your database and website.***
I would also eventually need to request temporary access (WP-Admin and FTP) to your site. Preferably to a test site where the problem has been replicated if possible in order to be of better help and check if some configurations might need to be changed.
I have set the next reply to private which means only you and I have access to it.