Starter Relay problems of the 2020 Toyota Highlander

The contact owns a 2020 Toyota Highlander. The contact stated that while driving at various speeds, the vehicle lost motive power and stalled. The contact was able to jumpstart the vehicle and the vehicle operated normally. The contact had taken to the vehicle to a certified mechanic who tested the battery and alternator but found no failure. The vehicle had not been diagnosed or repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 57,000.