Registration auto-fills with an alien name and email address

[neilpw]

I have just created a new meeting that requires registration.

When I test the registration link, I find that it is autofilled with an alien name and email address I have never heard of.

I deleted the meeting and created a new one. Same problem with same name/address.

I forwarded the link to my partner and she found that it correctly autofilled with her data. 

Can anyone explain what is going on and how I can fix this?

Thanks, Neil