Same colour name - different codes - different results

I recently set out on a mission to re-paint my entire two bedroom double storey townhouse. After much research and asking around and looking at swatches I decided on the colour antique petal for its light grey undertone, yet still bright and white.

The bathroom was being renovated by a contractor who's quote included painting the non-tiled bathroom walls. They asked what colour I would like and I told them antique petal. They painted it and it looked amazing!

I had to purchase all the paint for the painter who was coming on the weekend, and bought all the Plascon cashmere antique petal from builders warehouse in North Gate. (Phew - $$$)

The painters got going and on my return at the end of the day, the place was PINK!

I could not stop seeing PINK, no matter what colour I put next to it. Now what has happened here? both the colours are Plascon (bathroom & rest of the house) and both are Antique Petal. On closer inspection, and after complaining to builders warehouse that they have mis-mixed the colour, it was discovered that there is an Antique Petal with two different codes! The one has a "chalky pink' undertone to it and the other forms part of the architectural range (amazing - the bathroom colour). This is most definitely NOT what I wanted and have a freshly painted flat in PINK with a beautiful grey bathroom.

I wish to express my frustration, that asking at a paint store for the name of a paint can lead to two complete opposite results, and neither advised that there were two options. Either the names need to be changed or the shops need to be informed clearly to ask which code/range.