Are you colorblind? If not, then maybe the test block has faded with age.
I have seen ads for some optical tester, but I have never seen one in person. You fill test tubes and add reagent, then stick them inside and it reads and gives you a number. You might want to start googling for it.
It would be nice if someone made a pH test as foolproof as the FAS-DPD chlorine test, wouldn't it?
Reading the colors on the PH test gets much easier with practice. It is best to hold the view tube up to a white surface that is lit by direct sunlight. Good lighting makes it simpler to distinguish the colors.
If you really can't make the colors out, there are some alternative ways to measure PH that give direct digital readouts, but they cost around $100.