I have often asked clients to double check their junk or spam folder, sometimes it is filtered there. You can ask her to send you an email and copy & paste her email address into her account profile just to double and triple check there are no mistakes. We see so many people using zero and O and forgetting to specify. You can also ask her to open the search option inside her email account and search for one word in your business name, i.e. plumbing, electrician, pumpkins. Hopefully there's a word that isn't commonly in their daily emails and yours pops right up for her.

If none of that helps, send yourself one to be sure they are going through and you don't have system problems. If all else fails, click on the option to copy invoice link. Then you can include it in an email you personally send her, you can paste it in a social media conversation also if need be.

We've had to use every one of these for different clients over the years. We haven't found one fix that works for all of them yet.

Good Luck!