I see this a lot as well. If you log into your GoDaddy account via a incognito/private window, it usually allows you to make the changes. It's a caching issue with modern browsers and the GoDaddy site. I'm not sure if it's something that can be corrected really from GoDaddy's end.
If that doesn't correct your issue, give support a call or hop into live chat for further assistance.
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Once your issue is resolved, please be sure to come back and click accept for the solution