you should go over Chad's video again I think you got your notes wrong
the TLC plate is made of silica/cellulose/aluminum oxide which is a polar plate
so polar molecules will be attracted more to the plate so it will move less along with the solvent
whereas the nonpolar molecules will be less attracted to the plate so will move more along with the solvent.
the polarity of the solvent affects also the distance that the analytes move
more polar the solvent is, the solvent will "disturb" the analyte molecules to be attracted to the plate so the analytes will move more than when the analytes are in the nonpolar solvents
so if your TLC result the Rf value is too big, than you just used too much polar solvent
and if your Rf value is too small then you just used too nonpolar solvent.