plascon / build -it paint

i bought 4 drums of 20 liter Plascon paint from Build-it paarl for exterior walls.After a week later at first rain paint started to run and gets the water to wall.I took pictures and take it back to build-it .They said they will contact to me ones they speak to Plascon .3 weeks later nothing is happening.nobody is coming back.Never again plascon or build -it