Welcome to the hobby. Here are some questions for you:
What type of lights do you have?
What type of flow is hitting this coral?
How long have you had it?
What's the water temp?
What's the SG of the tank?
How long has this tank been up and running?
When was your last water change?
Most Leather Coral will go through "pouty" spells. During the normal "pout" the leather is expelling it's outer slime coat or "sloughing off" it's protective layer. This is only way a leather can self clean it's skin and get rid of any buildup on the coral. This "pouty/slough" stage should only last a few days and afterwards the coral will be better than ever. Just like we humans are right after a nice long hot shower. Good to Go!
They need some "decent" flow to help them "slough off" the protective coating but not so much as to blow the whole coral around and agitate it more.
Unfortunately this is also what the coral looks like when it's on a decline due to poor or incompatible water conditions. So wait a few days and watch how it acts. If you see it's not bouncing back you might need to take action. We always removed Leathers as to not pollute the tank. I don't think (
personally never had it help) that fragging a declining leather coral will help. They tend to be all or none unlike some stony coral where you can frag a declining section to save the rest of the colony.
Here's an article that might help with Leather Care:
https://reefbuilders.com/2015/09/30...corals-sarcophyton-lobophytum-and-sinularia/#
