If it worked before and has stopped now, there must be something that has changed.
As you are using PHP Mail, I guess your hoster blocked you from sending emails because of the amount.
Help us to help you!
Provide your LS version and where it is installed (own server, uni/employer, SaaS hosting, etc.).
Always provide a LSS file (not LSQ or LSG).
Note: I answer at this forum in my spare time, I'm not a LimeSurvey GmbH employee.
ljarbeau wrote: I can't solve why they aren't coming thru
Coming through can mean anything from not sending to not receiving.
PHPmail from a shared hosting is not recommend. You will have to ask your provider for more details about how phpmail is configured.
You can reduce such issues. Create an emailaccount for LimeSurvey and use SMTP inside LimeSurvey. That ensures that emails are really send via an emailserver and not via the webserver. Webserver are often not configured to send emails properly.