Replaced turn signal switch, but now it won't cancel?

I replaced the turn signal switch and it works, but it does not "cancel" when returning the steering wheel to center. 1989 Ford E 150 van, 5.0 liter, w/tilt and a/c. Part is new, ordered from RockAuto.com for $100. Switch has a center ring which rotates with the steering wheel. There's a spring loaded post on the center ring that engages a slot in the rear of the steering wheel. With the wheel off, I can engage the turn signal, then turn the center ring by hand and it will cancel the turn signal, as expected. When I install the steering wheel I can look through the slot next to the Hazard Warning switch and verify that the post engages the back of the steering wheel, and that the ring rotates with the wheel when I turn it. With the wheel off, the cancel works. With the wheel on, it does not. Any ideas? Thanks

Added (1). What I called the center ring is actually called the "cam" in mechanics parlance.

The cam may have broke in the steering column The cam that cancels the signal. Its not hard to replace But you need a wheel puller Other than that Maybe something is stuck in the lever I drive ford trucks too And that has happened to me I used to keep rubber bands on the signal lever and over time the bands got into the mechanism i had a 90,91 a 93 a 95 and still have a 97 HD F250… Yes its called a turn signal cancel cam. The cam it self can be worn The half moon looking white plastic Piece is the cam itself. Then you have the lower plate under that with the wires for the electrical Is it on correctly? I've done a few and never had problems. If you can look up a break down or if you have a book even better You honestly may need to replace the switch too The plate the cam attaches too Thats how i usually do it By replacing the whole thing Look close at the lower plate is there any mounting studs or pawls gone off the switch plate ( lower plate ) There's a detent basically a means to hold it in place until the Pawl Or detent ( A detent holds something in this case a turn signal switch Technically a detent is found in trannys or hydraulic stuff But its the same principal It releases at a certain point or pressure basically ) that lil deal can be either gone, worn out or broken. I think you should remove the whole thing and then Put it back together If you have a book or look up the breakdown on the net Just type in Ford trucks With your year turn signal switch/cam Then go to the images I found it pretty quick honestly its a easy thing to do Maybe you are overlooking something or the switch plate is worn out too too Those 2 pieces should be replaced at the same time Even though they sell the cam separately i just get both pieces with the cam attached to the switch p[late already I think thats the problem or Its installed wrong Best i can offer you my friend Hope you get it figured out good luck okay sorry you got the whole thing new then Its something in thye install Remove it then do it again Also what about the back of the steering wheel is something there causing this Cause i'm stumped now Also did you have the steering wheel on all the way It won't work unless its seated correctly Half way or even 3/4 on the shaft it won't work the wheel must be seated down all the way for it to work

Thanks for the answer, but the cam is the center ring I mentioned. (forgot the name- I'll Edit my question to correct it). It is also new with the new switch. I tried using the old cam with the new switch, same problem. With the steering wheel off and turning the cam by hand, it works as expected. With it on it does not. Tried removing/reinstalling it multiple times. Have verified that the cam moves when moving the steering wheel. (obviously I have a wheel puller) And no, nothing has gotten stuck in it.

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