Not receiving any e-mails anymore all of a sudden

For a while my client is not receiving any mails anymore when someone successfully sends an order.
I have tested this myself, and the customer receives the confirmation e-mail, however my client does not. No mail is stuck in a spam folder or whatsoever, it seems it is not being send at all, even after adding my private e-mailaddress to the recepients as well.

My clients website is:

It is being hosted at GoDaddy.

https://www.ads-software.com/plugins/woocommerce/