Fret level with possible neck warp?

Hi everyone!

I have recently been learning how to fret level and encountered this Fender Jaguar that even though the neck is fully straight, in around frets 13 to 18 there is a bow. No matter what I do the sanding beam doesn’t touch those frets. I could keep filling but then I might take too much meat from all the other ones.

Any ideas on what I can do here?

Image https://drive.google.com/file/d/1CUR22ozwFGvdnx2gplm2DsjUezwKjOZQ/view?usp=drivesd k" target="true">here

thanks a lot!