Taylor K-2006-SALT FAS-DPD, 9-in-1 Pool & Spa Test Kit, Free & Combined Chlorine, pH, Acid & Base Demand, Total Alkalinity, Calcium Hardness, Cyanuric Acid (CYA), and Chloride (Sodium Chloride).

I would not rely on test strips. They are usually not very accurate. Get something like this: https://www.amazon.com/taylor-Taylor-K-2006-Salt-Test-Kit/dp/B014PKXEUI?sr=8-1. Most important is CYA. CYA can bind free chlorine, rendering the sanitizer ineffective. Get a good test kit and post your results. Best to rule out the pool water as an issue.