A chatty first grader - what would you do?

I am a parent - I got the dreaded Principal email today that my child (6) has been talking during class when the teacher is speaking. We knew she has trouble following instructions - its a daily topic for us at home, we talk with her everyday about control, saving her conversations for lunch or recess. But she is still a 6, almost just 7 yr old.

because this was her 2nd strike, i got email from the principal. To me principal level emails are reserved for more serious issues. Trying to wrap my head around this situation but I am also a worried parent and want to help my child. What can I do to support her?