WHY CANT I APPLY FOR A FAMILY REUNION VISA AS A NEW APPLICANT?WHEN CAN I APPLY

I'm a Ghanaian,my wife and child stays in china .I applied for a family reunion visa since entries have been reopened after covid
I filled the form online and got a date for the interview,when I turned up for the interview, I was told I can't apply in the first place because I'm a new applicant. All my docs that were legalized will expire if I'm not able to apply in time . whats the reason why I can't apply as a new applicant?
And when can I apply again?