Onan generator fault 47 model 7HGJAD-2139K

My wife uses this generator in a mobile grooming van. So the last month we have had this fault code 47. It would stop after about 5 mins of running. We brought it to a generator shop and they said we needed to replace the tensioner. They said since they had to pull it I should go ahead and replace the coils and belt. I said ok and had it done. Took it home and used it for maybe 20 hours and it started doing the same thing. Brought it back to them and they said they had to replace the igniter. Got that replaced and brought it home again. 5 days later it’s doing the same thing! I don’t know what to do. It seems as though they are just replacing thing just to replace them and not doing a thorough diagnosis. Any help with the issue would be highly appreciated.