Shriveling seedling, what is happening?

[creator22]

My seedling in a mix of organic soil and perlite for two weeks now, is shriveling up. It's 84F and 64% humidity in my room. Humidity is usually lower but it's been rainy here. I've read the problem is too much or too little light, or too much or too little water, or too much or not enough something else, and not sure where to take it from here. hoping there might be a rescue possible but not very.

This plant's friend, right next to it, under the same lights and in the same soil mix, watered identically, etc. is doing great about 4" tall, multiple real leaves. I'm new at this. Thanks.

 

[Cbdfool]

I’ve had luck below around 70 degrees and lower humidity with a plastic bottle bottom over the top of it to keep the soil moist. Funny the one next to it is doing fine.

 

[Edinburgh]

Your running to hot, rh is high but they usually fight thru that, put a fan on it and raise light.

 

[mysticepipedon]

I can't tell you what went wrong, but I can tell you that I would pull that plant and start over.

 

[crossfader]

You're beating a dead horse in trying to get that to turn around. Cut losses now and start over but watch those temps!