According to the FDA, the pumps may have a broken or missing retainer ring, an issue that can cause the over- or under-delivery of insulin. That's why the FDA makes this a Class 1 recall, which means, "use of these devices may cause serious injuries or death". Severe hyperglycemia can result in a loss of consciousness, seizure, and death.
Medtronic began directly notifying patients and doctors on November 21, 2019, that there were potential problems with the pumps.
Check the pump and retaining ring every change established to verify that the tank is properly locked.
In a letter to customers, Medtronic said, "There have been reported incidents of a loose reservoir that can no longer be locked into the pump. The retainer ring can be broken, for example, as a result of dropping or bumping your pump on a hard surface".