Then why don't FDA just fully approv the vaccine? Apparently, FDA hasn't approved the vaccine. I'm not an expert in the vaccine. So, I won't debate the details

Then why don't FDA just fully approv the vaccine? Apparently, FDA hasn't approved the vaccine. I'm not an expert in the vaccine. So, I won't debate the details. It is very jarring that FDA/CDC claims the vaccine is safe, but they refuse to approve the vaccine.