Make it possible to check out in your shop with a phone number (verified by OTP - optional) instead of an email OR combine both fields and let the customer choose.
There are customers who want to provide either email ID or phone number for a faster checkout process. Also there are customers who don't have an email address or are reluctant to provide it because of potential spam or marketing emails. will allow such customers to place orders in your store, as it gives a possibility to check out without filling in the email address field or provide a single field for email ID or phone number and let the customers decide the way they want to checkout in your store.