Welcome!
Yes we can help.
Step One: accept that the pool store exists to sell chemicals. When you walk in, what do you see? Shelves full of chemicals. Stacks of buckets of pucks. The air smells of pool chemicals. They may or may not offer sound advice, but you can be sure they will try to solve your problems with more chemicals. You've seen with your own eyes that it doesn't always work. So stay out of the pool store. Whatever chemicals you might need can be purchased much cheaper at the grocery store, the hardware store, or the big box store.
Step two: Buy a
proper test kit! There is no substitute. No one cares more about getting your pool right than you. The free testing at the pool store isn't really free. Go tally up what you've already spent. You could have purchased the Cadillac of test kits and probably all the chemicals you'll need for what you've already spent. Test strips won't cut it. They get ruined if they get damp, the colors can bleach out or bleed, and they usually have useless scales like 30-100, when you need to know +/- 10. Yes, a good test kit is a big chunk o'change, but if it saves you one trip to the pool store, it's paid for itself. Order a TF100 with the XL option and you'll be set for the rest of the year and probably partway into next.
Step three: test your water and post results here and we will advise you.
My gut feeling, based on hundreds if not thousands of threads from people in the same boat as you (wallet empty, pool still not clear) is that you have too much CYA buildup from years of chlorinating via pucks and shock powders and this renders the chlorine you added useless. But again, this is just a gut feeling. Test results will eliminate any guesswork.