paph lawrenceanum is notorious for climbing although it is a lightweight when compared to things like
phrag schlimii. lawrenceanum is a component of almost all the maudiae-type hybrids, and some of the other species may also do that from time to time.
options:
adding media is one option but if you cover the old growths you may increase their risk of rot. one thing to do is to slant the plant while repotting so that the plane of the growths is horizontal.
or just stuff a wad of sphag there so the roots grow down through them and into the media. unless you're in a greenhouse, though, you'll need to moisten that wad twice a day.