Hello @SBritton ,
The reason you're seeing your email inserted automatically is because PayPal is recognizing the device that you've already logged into it on (or that you've recently logged into it on). If you attempt to register in Incognito or an unrecognized device / browser / IP address, it'll show the email address you entered for registration. For example:
If a person registering for your event doesn't have a PayPal account / is using an unrecognized device, PayPal will ask them to either login or checkout as a guest (sometimes displayed as that bottom button). If you have additional questions about how PayPal checkouts work, I'd advise reaching out to PayPal's support.
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