1. You don't need the word "already" as it is implied in the past tense of the word "emailed" (if you have emailed, you have (already) done it) 2. Use the word "but," after your comma: "I have emailed customer service about it, but they haven't talked with (or spoken with) her yet." 3. "This has happened three times already, (good use of already here!). We've started grammar and not receiving her emails is impacting her progress. We are both getting pretty frustrated about this."

Hi Dor Bitan, I am not the best person to help you with grammar. Instead, I will try to help you with your issue. - Check with the student if he/she can receive e-mail from someone else. Maybe he/she inbox folder is full. - Ask the student to verify the other folders where your email could be, such as the spam folder. - Ask the student to send you an email, if you receive it, reply to the email and recheck the student inbox email. - Sorry for this one, but make sure you are spelling the correct e-mail. For some reason, you can not be getting error. - Can you see any email saying your email sent to the student can not be delivered? Hopefully, it can help you.