Baby Dam Product Issue

I bought a Baby Dam through takealot a few months back . I've been too busy to do anything about it . but have just reviewed telkom now and thought that maybe revising Baby Dam now would resolve the issue.

I bought the baby dam because of the raving reviews, I also wanted to save water when bathing my daughter. but this gadget does not stay in the bath . it pops off all the time . the first time it did it I reread instructions . looked at the instruction video too . but I had installed it correctly . still to this day , everyone I bath her it pops off . I don't even fill it to the "full line" . I've stopped using it because it too dangerous when the rush of water fills the rest of the bath after it pops off . it could possibly be my bath that's the issue and not the product . BUT it is advertised that it works in all baths ...its annoying because i spent over R500 on this item and I only have used it 8 times since I bought it and it just doesn't work at all .