Lambs Breath sprout failing to thrive

Lambs Breath plant now Day 21- with grow light 16 hours/day Inside. Adequate moisture. No new growth after 7 days. Looks the same as last picture posted. Still green. Unless you have an idea, I think I’m going to lose this one. Others plants are 15 cm tall

Thanks for the suggestions. I have removed the 2nd shell case. And misted with water. Covered with a bottle- dome to maintain moisture.

Hello.. Hope you are well.. U cud try putting a propagator dome(or bottle) over her and see if she'll progress after a few days.. Leave vent open very slightly (or cut small holes in top of bottle).. The extra heat and humidity mite help kick start her again.. Hope she grows for u.. Stay safe n gud luck.. 👍🍀

Greetings, I’d be very concerned if I had a baby stuck in its shell after 20 days, anytime I’ve germinated and the shell is still stuck after 3 days I remove them manually, personally I’d really take your time and gently remove any remains of the shell to give her a chance to open her leaves, misting water helps get them off, without this intervention she’ll never get the chance to see the sun and in turn she’ll more than likely die, just my 2 pence! Good luck!

Not all seeds are created equal, just have to wait and see what she does. Luck my friend