What is your pool volume? How did you add your cya and if you added it to your skimmer to dissolve in the filter, have you backwashed any?

It may be that it just hasn't dissolved yet. It takes a long time. Or it may be that their result is inaccurate. CYA readings seem to be one that pool stores often get wrong.

Is the pool looking better? Keep at it. You're doing the right things.