No reverse 06 Pacifica touring 3.5l
 

I bought my car about 2 years ago, about 6 months ago my reverse went out it'll go to reverse on the shifter but then acts like it's in neutral, it goes into every other gear and drives but I don't understand the no reverse. I'm on a fixed income and really hope there's a solution besides changing the tranny.
Any advice would be appreciated thank you in advance.
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