This kind of bag may be divided into two types, one is sticky, I once saw a bus. The master said it was feeding the fish, and the fishbone stuck in his neck. For two years, I can't manage it, and most people can't operate it. Another condition is inflammation and cyst. What kind is it? Touch it yourself. If it is hard and you have fed any fish or shrimp, it may get stuck. There is nothing I can do, and I can't help you. The other is a cyst. You feel soft and there is no hard object. This kind needs treatment, mainly anti-inflammatory drugs, oxytetracycline and the like, or amoxicillin. Don't overdo it. If it doesn't work, you have to ask a veterinarian to operate it.