Noticed distressed leaves. Can anyone tell me why ...

Looks like a couple things are happening to your plant here . Firstly like Athos and the scientist have suggest is that you have the start of leaf miners , you are going to want to treat this immediately !!! You can do it in a variety of ways , first and easiest way at this stay would be to go through your plant and remove any affected leaves if you choose this method you must be very very diligent and get ALL the affected leaves . Another good option is neem oil but instead of spraying it on like you would traditionally you would mix your solution in a bowl take a micro fiber cloth and apply it directly to the affected leaves , this is the more controlled way to do it with neem oil this late in the plants life . You don't wanna spray it because you have flowers now and you dont want them to taste bad or get covered with an oil lair from neem it would just be a waste of all that hard work you've done so far . Thirdly the last method takes alot of time and patience so people don't really do this anymore , you could take ice cubes and hold them over the affected areas the cold will kill pretty much all insects out side and inside the leaf , the only real problem here is that it damages your leaf reguardless and if you have an infestation your going to go through a bunch of ice cubes so its just not worth it but it still works as a last resort type thing if your ever stuck . Moving on to the nutrients now , I can see brown spots in the center of your leaves which leads me to believe this is PK deficiency you should up the dossages of your nutrient bloom solution by a little bit . You may also want to consider lowers the "growth" part of that formula . You're plant is showing the very early stages of nitro excess with the clawing and the tips almost curling , if this continues you may run into nutrient burns . Its also important to understand that your medium will retain nutrients longer then soiless mix or hydroponic systems , so my suggestion is to only use nutrient water every 2nd or 3rd feeding this way your plant can use up most of whats in your soil before you add new ones in , between nutrient watering water them with PH corrected water so they can still continue to draw the nutrients from the soil without suffering an lock outs or unwanted stresses . Over all I think your rocking and rolling just got a few things to fix up and 1 major thing to fix up and you will be right back on track ! I hope you find this information useful on your quest to the finish line ! -Happy Growing!

Hello BijoyBhatia ! These are leaf miners. In general you shouldn't spray with anything during flower but if i was you i would definitely spray with bacillus thuringiensis. These larvae can make very big damage to your plant if you don't treat them properly. They can stress the plant so much to the point it can become hermie. Also they will start to poop inside the buds and you will end up with a very bad quality weed with seeds and poop.If you spray now bacillus thuringiensis will no longer be on your plants until you harvest (at least not to the point that it will be bad for your health or for the smoking experience) and even if there is some i believe its better from poop. Its a natural bacteria all over the nature. So i believe that you should spray even for one time. Happy growing ! 👊

There's a bit of clawing, which is a sign of nitrogen toxicity, so you might want to lower the amount of it you are giving the plant. There's also clear signs of leaf miners, they are a kind of larvae (usually of moths) that live inside leaves tissue. Neem oil works as a treatment, but at this point in flower I would not spray anything. What I would do is either pluck the affected leaves or check the underside of the leaves and remove them one by one (requires a very sharp eye or a loupe).