https://www.amazon.com/Gordon-GlassTM-Sliding-Shower-Bottom/dp/B09HV6Z2GD/ref=asc_df_B09HV6Z2GD/?tag=hyprod-20&linkCode=df0&hvadid=598349219951&hvpos=&hvnetw=g&hvrand=7338191621255819701&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=9018360&hvtargid=pla-1668546616779&psc=1

This looks like the piece. So I would assume check there is no caulking holding it, then slide it.