Why do soaps not work in hard water?

Explanation

In hard water Ca,Mg-siddolved salts are present.`Ca^(+2),mg^(+2)` ions form insoluble Ca,Mg, soaps respectively when sodium(or) potassium soaps are dissolved in hard water.
`underset("soap")(2C_(17)H)_(35)COONa +MgCl_(2) to 2NaCl +underset("Magnesium stearate ( insoluble soap )")((C_(17)H_(35)COO)_(2)Mg)`
1)These insoluble soaps separate as scum in water and are useless as cleaning agent.These are problematic to good washing because the ppt adheres into the fibres of cloth as gummy mass.
2) Hair washed with hard water looks dull.
3) dye does not absorb avenly on cloth washed with soap using hard water due to this gummy mass.