Anyone using MacMail?

[question everything]

I am using it as POP (?) with my Comcast Internet provider.

All of a sudden I am not getting a regular alert about a monthly utility bill that I have been getting for 10 years.

The utility thinks that their email is being diverted into a junk mail folder. I don't have a junk mail folder in my system. Not that I am aware of it.

I asked Comcast but they said that since this is Mac Mail I have to ask Apple. I went to my preferences and saw that there is a whole section about junk mail so I unchecked the "enable junk mail filtering." Never knew I had it.

Now will have to wait.

Any other suggestions here?

Thanks