blocked emails from water utility

My water bill is not being delivered to my Comcast email.  I almost missed a payment and could have had my water turned off.  I changed my delivery email address and received a test email from the utility in my gmail account.  So it's being blocked by Comcast.  I used to get these emails in my Comcast account and they stopped about 2 months ago.  Domain is @schedulepayment.com.  The blocked emails are not in my spam folder.  I turned off spam blocking temporarily, had the water utility send an email, and I still didn't receive the email.  I'm receiving other emails.  I can't reach Comast support to help.