This soap holder is my first 3d model. I designed it to fit to one existing hole in joint of my bathroom and it fits perfectly. Maybe someone can use it as well. Feel free to copy the model from my Onshape profile and do your adjustments. :)

https://cad.onshape.com/documents/34b1064ae29216dd8c60cd34/w/9b334b67e48cd679e51b393c/e/85185eaee806c6ebee6149fc?renderMode=0&uiState=671ff3b57c5ab8658fce6cad

I printed it with layer height 0.2 and infill of 15%.