The "dropped" email response indicates that a previous email that's been sent to an email address has failed, and that our mail server is no longer attempting to send to that particular address.
A couple of ways to ensure this doesn't happen is to check the email address to make sure it is spelled correctly, to check the size of any documents that may be attached to the email (we recommend trying not to send documents that are 15Mb or higher, as it can slow the ability to send the email which may result in it timing out / failing), or check your default message or notes that are connected to a quote or invoice and make sure there is nothing that may trigger a spam block.
If the email address is correct and it continues to drop emails, it may need to be cleared by our mail server. You can contact support viz the widget, by selecting the circled question mark in the top right corner of your Formitize portal and selecting Support. There will be an option in the widget to Contact Support. Otherwise email [email protected]