tulips

I once had a cinnamon vine,Dioscoria batatas.It started to sucker from it's huge main tuber,so I tried to remove it,but I never located the central main tuber,so it took years of pulling out before it finally gave up the ghost. It produced many small, potato-like tubers all along the vine that fell off and grew into new plants.Thing is,the fragrance wasn't really all I had it hyped up to be, and really nothing to write home about.Dioscorias can be very invasive.This was in Illinois,40 miles south of Chicago.

I wonder if this is Richardia brasiliensis (stems densely hairy toward the base) or R. scabra (stems modestly hairy or glabrous toward the base). Richardia does have flowers with 4-6 lobes. Similar genera, such as Diodia, Diodella, Mitracarpus, and Spermacoce have flowers with 4 lobes.

Thanks for the response. If it is a root issue, how would you ID/treat it? This produces a ton of fruit and has been very healthy as recently as one month ago so cannot imagine it is just at the end of life.