Any help of what is causing the yellowing of my se...

I suggest using a dropper. I literally dropped around 1ml to 2ml of water around the seedling. The I went up from there to half of cups etc. Cote leaves generally fall off and die fairly quickly. Keep an eye on the main leaves for signs of distress. As long as you fixed the ph and back off on watering, you should be A O K👌

Wet feet you have a root problem form over watering. Dry her out some and raise your RH to 60-70%. Give her a misting of 25ppm of epsom salts under the leaves when the lights go on.😎

Hey Deez, It looks like you are overwatering. Seedlings only need a little bit of water. When your soil is too wet, the roots suffocate from lack of oxygen. I would let it dry out until the first inch of soil is dry before watering again. She will improve and start growing again. Your pH is also a little high. Plants in soil seem to like the pH around 6.5. Good luck!