I cannot receive group emails from my church

I cannot receive group emails from my church.  I receive individual emails or small group emails, but not the ones I really need to do my work.  How do I fix this? The emails are not in junk or spam. They just disappear into thin air. The sender has no idea that I have not received the email.  The church office has tried taking me out of the computer list and putting me back in, but nothing helps.