My Dolphin, while it runs and has no mechanic issues, has a 3 yr warranty (1 yr left), but spends more time on drains than cleaning, defeating the purpose. It was my first robot so I didn’t have enough experience to know what I wanted or needed.
I had the same issue initially. Don't know if you tried this or if it'll work for you, but someone advised turning off the main drains while robot was in use. I tried that and it hasn't been a problem since. The vac still gets hung up occasionally, but without the suction it frees itself pretty quickly. At least that's been my experience.