Our Company emails are being marked as Spam by comcast

@ComcastSPAAbuse Hello, several emails from our company domain are being marked as spam. We have filled out the block list form, and our IP addresses are not being blocked. This started happenning on August 25th, and more than 80% of our comcast guests are not receiving our promotional emails. Can you please look into our domain and see why only some of our emails are consistently marked as Spam.