Hi Clifford,
Thanks for reaching out. If the customer has forgotten their password or email used, they will have to reach out to IBM support from a colleague's email that is authorised to access the account. The customer can also try resetting the password at the login portal, by typing in what they think the username might be (ex. email address or commonly used username). If those fail, your customer may have to try to escalate further with support, to see if there is another method of verification that can be used.
To note, as an authoritative DNS provider, NS1 does not control the domain, only the DNS for Zones and Resource Records.
Thanks
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Charlie Sprankling
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