emails are sometimes sent to Spam folders or blocked by incoming servers. We know that this is happening once in a while and we can't really control it.
This is why we have created the Progressive Web Apps that give you devise notifications as well as emails. All you have to do is click on Enable Push notifications button at the back end or the bell in the top right corner at the back end (https://booking.drivenot.com/en/documentation/87-progressive-web-app-pwa-for-admins).
Your customers can now download your booking form as a Progressive web app and install it on almost any device. They can also opt-in to receive Push notifications regarding their orders.
To activate front end booking form mobile app you have to go to the back office > Dashboard > Settings > Mobile app. Here you have to upload just a few different sizes of your company square logo and the system will do the rest.
Please also check your Spam folders as emails are stuck there sometimes.
Hope this helps.