I thick my ganglion cyst is going down as fast as it go up if it is why or how is it go down as fast as it go up it on the top of my wrist?

Fluid build up: What makes it go up is joint fluid building up inside of it and when the fluid goes back into your joint, your body will absorb it and your cyst goes down. The ganglion cyst communicates with your joint.

Synovial fluid: Fills ganglion cysts. These cysts are fluid filled sacs and synovial fluid is what lubricates the joint, fluid enters the cyst through a tiny attachment from the joint and makes the cyst large . This is why activity or force seemingly makes the ganglion larger as more pressure in the joint leaks into the cyst. Typically it's a like one way valve into the cyst but they can drain back spontaneously.