Anatomy scan Q’s

Has anyone ever had the tech not be able to tell the gender?? I have an anatomy scan November 19th and now I’m worried that baby may hide themselves and I’m wondering if we should try to do a separate scan earlier for gender 😬 im super excited to find out on our mini vacation the 21-25 and I don’t want to risk the tech not being able to tell!

I will be 20+2 at my anatomy scan, my son never had an issue he showed us everything but every kiddo is different 😂