Why I can't use my domain ".com.br"?

Hi. I’m from Brazil, and I have a domain “.com.br”, but when I try to redirect to Infinityfree DNS refuse. Does Infityfree support “.com.br”?

I’m sorry, but what do you mean by “DNS refuse”? Would you say this article applies to your issue? Unable to set nameservers: DNS query refused - Docs - InfinityFree Forum