Masil 5 Probiotics Perfect Volume Shampoo 500 ml vs. 300 ml experience

So, I've been using this shampoo for over 3 years and loved it. But this whole time, I used the 300 ml bottle. Until about a month ago, when I decided to spare on shipping cost and buy 500 ml.
And I'm a bit shocked? It seems like it's diluted compared to the 300 ml? I used to use about the amount of a chest nut and now I need twice the amount?! It also feels a bit more runny.

Does anybody else have similar experience?