Lasagna, let's start with the filter. Is it dirty? Cloudy water is almost always dead algae and that will clog a filter fast. That impaired flow can mess with the sensors on a SWG.
Meanwhile, assuming you have done the pH adjustment, then toss some more chlorine in that pool.
With FC 0 that algae is going to come back to life with all this sunshine. We still need to know your CYA (stabilizer) in order to begin shocking. Without a proper shock, you are just treading water with the algae going from green to white to green. I hate those strips for CYA, I found that they read 30 ppm as zero and so I'd prefer you take a sample to a good pool store for a better read. As long as they don't use strips also.
The reason we need to know, and we don't want to guess, is that if you add too little chlorine to the pool, as you have seen, you never get the problem fixed, you just waste time and money. If you add too much (way too much) you could damage the pool. So, test, and then treat. But you need a trust worthy test. Not a guestimate, which is what those test strips become as you try to judge colors. (this looks 25% like burnt orange and 75% like plum)