Webhook Create Order doesn't have customer email

[IvanPro]

Sometimes webhook 'order/create' doesn't have customer email? Why this happens? Webhooks docs says that it will be here and shopify also ask for email on checkout page. Maybe I should use another webhook for this? 
My goal to send email to customer while order is created.  

PLease advice)

[Zameer]

Hey there,

Orders created through Shopify's online checkout require either an e-mail address or a phone number. It's also possible to create orders through the API where neither are present. 

If you are receiving webhook notifications for newly created orders where the e-mail parameter is blank, then there must not have been an e-mail associated with the order when it was created.

[BogdanM]

Hi,

Please look here.

I quote from that page: "The order might not have a customer and apps should not depend on the existence of a customer object. This value might be null if the order was created through Shopify POS."

Could this be your case?