Can't add domain

Website URL

ustchile.page.gd

Error Message

“The domain is not registered. Please register the domain before adding it to your account.

Other Information

I’m trying to add the domain unionsocialistadeltrabajo.cl and it’s saying it’s not registered, even though it is registered for 2 years on NIC Chile and I have pointed the name servers to ns1.infinityfree.com and ns2.infinityfree.com.

What must I do?