2002 pt cruiser will not go into gear!

Just replaced the transmission solonoid and it ran great for a couple weeks. Out of nowhere yesterday it just stopped going into gear. I can shift easily, but it’s like the car is in neutral. It has almost a whine sound when I try to engage it. Had fluid and filter changed at the time of replacement and just checked it and its fine… help please! Am I looking at a hefty bill to fix this problem?