In the part datasheet it's stated: "V IN undervoltage fault. VIN_UV is set when the input falls below V SLP . VIN_UV fault shows only one time. Once read, VIN_UV clears until the the UVLO event occurs.".
Since I don't have anything connect to Vin I can't understand this fault, but what is troubling my mind is the fact that VIN_UV is not cleared after the FAULT is reported by the INT pin.