Reinstalling Catalina on MacBook Air

I want to reinstall Catalina on my MacBook Air without deleting all the data on my hard disc. I have started in internet recovery mode, and get to the page where it asks me to choose the disc on which I want to do the install. But there is no disc.

I don't want to go back and erase the disc. Is there a way to make the disc appear at this point so I can continue the install? When I give up and restart, it does start up as normal.

I ran Disc Utility First Aird and all was fine.