2006 MERCURY MARINER LOST REVERSE IS THIS PART OF THE RECALL

I am not aware of any transmission related recalls for a 2006 Mariner. https://repairpal.com/mercury-mariner-2006/recalls You could have an electrical or mechanical concern with your transmission. Testing is required. Ensure your fluid is full and clean.

Have qualified personnel perform a 'manual low' test .. This is done during a simple test drive .. IF no manual low - transmission needs to be replaced or rebuilt .. You'll likely get more knowledgeable assistance from a transmission specialist. (AAMCO Transmissions used to do this for free)