I want to make sure you and your customers are receiving their invoices, @emmashairstyle. We're going to perform some troubleshooting steps to determine why it's happening. Let me discuss this further.
First, please double-check that you are using the correct email address and resend it.
Then, we can refer to this article for e detailed steps and information on how to fix the problem and it's possible reasons: Not receiving your sales forms or reports via email?
Also, I'm adding an article for additional resources. This can also guide you on how to troubleshoot email delivery issues: Delivery Errors when trying to email a sales form.
For future reference, check out this article on receiving and recording invoice payments, including full and partial payments, editing or deleting payments, managing tips from overpayments, and handling credits.
Feel free to contact us again if you have any further questions regarding emailing invoices, I’ll ensure that everything is addressed for you. Take care.