Everything you're feeding is organic. What does that mean?
It's not readily taken up until microorganisms break it down into smaller pieces.
Why does that matter?
Generally takes two to six weeks for the organic matter to be fully broken down in the soil and become available to plants. Feeding organic nitrogen 3 weeks into flower is not helping, plant doesn't want any more nitrogen, skewing your ph
Nitrification is the process by which plants convert organic nitrogen firstly into NH4+, then process that into NO3-, Different forms, different charges, different ph.
At a pH of 6.2, nitric acid is about 20% as efficient as it would be at 7.0.
Everything you have ever fed has been organic, your running pH of 6.2, CEC of the soil is full, microorganisms just continue to break down organic nitrogen into the soil, skewing the ratio of PH dramatically. Your EC within the medium is full, as the plant uses less and less more and more will remain in the soil. This will turn your medium acidic. When ammoniacal nitrogen exceeds 20% if the total nitrogen, it can lead to various detrimental effects, including inhibited growth, reduced photosynthesis, and potential tissue damage. Excessive ammonium can disrupt nutrient uptake, particularly calcium, and lead to an imbalance in carbon and nitrogen metabolism.
Different forms of nitrogen have varying degrees of mobility within the soil. Nitrate (NO₃⁻) is highly mobile and easily leached, while ammonium (NH₄⁺) is less mobile due to its attraction to negatively charged soil particles. This difference in mobility affects how easily these forms of nitrogen are taken up by plant roots and how susceptible they are to loss from the soil through leeching.