songs on iPhone 12 not showing up in iTunes

I had to retire my trusty iPhone 6+ after 7 years of faithful service. I upgraded to an iPhone 12 and while the 2k songs that were on my iPhone 6+ are on the iPhone 12 and will play, they do not show up in iTunes when the iPhone 12 is connected to my Windows 10 laptop. There are over 30k songs in my iTunes library on an external hard drive and i manage what's on my phone manually.