Diagnosis issue. Impaired Insulin Signaling

Does anyone have experience with what seems like an Impaired Insulin Signaling problem. If I eat too much sugar/carbs, OR if I have an infection, UTI, Pneumonia, Covid Shot, I have an episode which includes Dumping, nausea, vomiting, passing out, can’t pick up head, 4-6 hrs. Fluids solve problem Glucose is normal. Considering Euglycemia Ketoacidosis. Fits symptoms But not tested, 7 doctors are baffled. Still searching for answers. Over 10 years.