Can't add apex domain through API

I was trying to update the main “A” record for a domain through the API. I started by deleting the existing record. When I went to POST the record with a new IP address, I was told the name was invalid:

{"code":9000,"message":"DNS name is invalid."}

I tried "name": "@" as described in the docs and also "name": "example.com" but got the same error message for both.

Any suggestions?

Thanks,
Adam

Can you share your full API request minus auth headers.