There isn't a lack of communication though. You probably were phoned and you were emailed
the school are well aware that many of us parents have communication issues
So yes, there was a lack of communication. The school are aware that parents have communication issues. If they couldn't reach op by phone (which is an assumption that many have made, op didn't say that they had attempted to call her) they should have backed the email up with a letter! Op says her daughter told her, so there is NOTHING to suggest that her daughter would have binned the letter at all.
Most here are making assumptions about things that op hasn't even mentioned!
Schools are not perfect you know, they occasionally fuck up. In the case of my 5yr, whose teacher (not her normal teacher, a stand in) failed to notify me & the leadership team that my daughter banged her head very hard at school. My 5yr old didn't tell for a day or so, so it is lucky that she didn't start to show signs of a concussion, as I would have had no idea what it was, without the information the teacher withheld. The school have actually refused to use her again, because they were so angry that she didn't think it was important enough to tell us.
And before anyone says anything, she could have phoned, emailed, written in my daughters communication book (which I check every night), put a note in her book bag, asked the early years support officer to call me, or even told me when I collected my dd.
So yes, schools fuck up! Or in this case, I believe they just got lazy!