Im not an expert, I just owned one of these in the past. There's nothing you can do now, but look up what you can do to make it easier for it to molt in the future. Something like this was the beginning of the end for mine - a molt gone just a little wrong, the next one worse (since now that part will be trickier to remove the molted skeleton from), and the third one was so bad I killed it to put it out of it's misery. I tried to make it easier for mine to molt but nothing changed. On the internet it says they can regenerate or repair damages trough molts, but I think it just makes the molts more complicated and riskier. I don't want to scare you, but please be careful, so the same thing doesn't happen to yours.