Could someone help me to identify the issue my plant has?

Calcium being immobile fits as it's old growth primarily effected. Sometimes just tap water itself can be enough calcium and magnesium that you don't need to supplement. Is it actual deficient or has the pH skewed. You mention you switched to auto pots wickimg from bottom, then you flood fed from the top, doesn't salt build up in top layer of soil with autopots? I may be wrong but i thought it was a big no no. Also of you plan on using plastic autopots I'd drop your humidity to 44-50% greatly help wayer cycling through your plant due to evaporation. Wick rates and rate of which water stays in the medium is dictated primarily by your environment. If it's just a little too moist, it's not beneficial for tranpiration. Check your ph if it's OK feed calcium. If it's off , correct ph. Applying light foliar application of calcium to leaves will absorb almost instantaneous helping with the immediate deficiency until the medium is rectified. Good luck with your grow, she was looking great till this week. Best of luck 👍