If you have directed your domain to hosting at Hostgator by using their nameservers, you will need to manage your DNS with that provider. You won't see the DNS in the GoDaddy account. If you wish to manage your DNS with GoDaddy, you will need to change the nameservers to GoDaddy default setting and direct the domain to your hosting with the use of the A record. You would update the A Record to the IP address on the Hostgator server in use.
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