Please double-check this when creating your email address on GoDaddy after purchasing your domain.
Your domain name will appear in grey. You will be given an option to add a name like info, support, or your personal name before the @ symbol. Only enter the name you want before the @. Do not type your domain name again.
If you enter the domain name again, it will duplicate it, for example:
If this happens, you will need to purchase a new email address, as GoDaddy cannot fix this issue afterward.
Please double-check all options carefully before completing the setup.