I wish I could help and come by, but, ah, slightly wrong location here I guess.
I had a bubble coral for a few years. It surprised me on its overall hardiness.
I did end up losing it one day.
I'm not really sure what happened, but I suspect it was due to an ammonia spike when I took out a LOT of rock out of my tank (they were infested with mushrooms).
Basically, it lost its flesh and became a skeleton.
This doesn't sound like what you're describing. So .. I don't know if that means there's hope, that might be a bit of a reach. But yes, in the years that I did have it and it did fine, it would indeed go through periodic bouts of deflation, expelling out goo, etc. Not quite as often as what you're seeing, so I don't know what's happening in your tank.
Do you feed it? I should mention, that I regularly fed mine. Small pieces of shrimp is what I used, this was before I knew about mysis. If you could try feeding it, see if it will take food. Not too much. If it does take it, I'd feel better that it's probably just going through some kind of adjustment.
Basically, if the flesh isn't disintegrating off the skeleton, I don't think it's dying. But this is a guess on my part, without being able to see what's going on ....
Good luck.