yellowing leaves

Those look fine usually those first little pilot leaves are going to die off regardless she'll get darker as she works her way from 3s to 7s (leaves)

I dont use b52 as foliar spray. The soil I used is full of NPK, I think it would be enough for 2-3 weeks. Ph of water was 7.5, because of this some nutrients was locked I think. I corrected water to ph 6.1 and last watterings was with tis water adding b52, diamond nectar and calmag. I think to give them feeding in this week, 1/4 dose of 12-11-18 (yara complex) + micro + calmag

Ok... are you using the B-52 as a foliar spray as it's intended to be used? That is the only nute I see you using that has any NPK in it. I have only used a foliar spray as a quick way to get some nutes to my plants that need a bit of a "leg up" - it's not intended to be used as your main method of feeding. Since these are autos, though, you're ok as they don't like a whole lot of nutes for the first couple of weeks. I would look for another NPK nute (and Advance Nutrients has several to choose from) that you could add to your feeding and save the B-52 for when they need an extra little shot of something... When you find what nute you want to use, start it off at about 1/4 strength... you can increase from there if the nutes are tolerated well. But yeah, you're right in assuming it needs some nitrogen (N) but also phosphorus (P) and potassium (K) Good luck!

IMHO, Magnesium.. Try add some calmag

Ph of water was 7.5 now its corrected to 6.1 an last 2 watering was with ph 6.1, but leaves are still yellowing. may be it is lock down ? because the soil I used is full of nutrients and because of this a I'm not giving them NPK, only stims, Should I give them NPK or wait few days ?

Probably low on nitrogen. Don't overreact but do increase concentration of your fertilizer or frequency. If it has multiple parts, you could consider trying to limit how that affects teh overall mix or increase entire mix in proportion.

Hi there a little more info on your grow would be helpful.. but to me looks like its under fed maybe increase the feed a tad, normal the lower leafs start to yellow from the bottom when the plants trying to draw nutrients from the leafs to replace what the roots ain’t getting, Good luck 🌱

Diary is started, All are autos. It seems like N deficiency ?

Love to... but where's the diary for this grow? Is it an auto? Photo? You're needing some NPK nutes but the strength will depend on what it is.... autos should get about 1/4 strength, photos you can go a LITTLE bit higher to maybe 1/2 strength... Start a diary! Then when problems/issues/questions arise, we'll have as much information as possible on which to base our advice! Good luck!