How man sylanoids are in the transmission and what ae there purposes?

Hello, you probably do not have a solenoid issue and probably do have a hydraulic mechanical issue. Have a diagnostic test performed before doing anything else. From a servicing point of view, as a person who ran a Hyundai dealership service department, I cannot remember a single time where a car would not go into gear and was repaired without replacing the transmission assembly. Just my experience.