The .hu TLD registry has special requirements for domains before nameservers can be changed. Please set up the e-mail address email@example.com or remove all MX records from the domain www.yourdomain.hu as long as the nameservers are being changed. First, You just have to create the firstname.lastname@example.org email, then your registrar will let you change the nameservers, otherwise, they will not let you do that.
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