Royal Canin Ageing 15+

After the update of "ageing sterilised 12+" for my 16-year-old seniors, I tried the small pack. Since that went well, I bought a large pack. Unfortunately, there was another change in the formula and the kibble is now half the size. As a result, two cats keep throwing up the kibble and another one has diarrhoea – even after gradually mixing it with another product. The rest of that 4kg will have to be thrown away, that's €45 straight in the bin 😡