I am trying to send automated emails via Manychat using a custom domain. I have successfully connected my custom domain to Manychat, and said domain works well when I use it on other platforms, I have even tried with two different domains from different providers and keep getting the same error, and so the error has to be within Manychat.

Whenever and email is triggered, it is not sent, and I get the following message in my inbox: 

A message was received from this address by our systems that had errors in the SMTPAPI header, and cannot be processed due to the following: - The IP Pool name must be a valid pool name for your account. You provided pool_verified_medium If you require assistance in working with the SendGrid API, please contact us at support@sendgrid.com 

I have already tried to contact support@sendgrid.com with no luck.

I cannot find any information online about how it is possible to set the IP Pool name in my account in Manychat, or what this IP address should be set to.

Can someone please help me figure out where I’m doing something wrong?

Thanks a lot in advance