@jpnegron , Sergio Angulo , If manual transmission, try having some one rock the truck back and fourth while you try shifting out of reverse. If it does pop out your clutch/pressure plate/master/slave cylinder may be worn/faulty/ or have air in hydraulic system not allowing release. If it will just not come out of reverse suspect a damage/bent shift fork inside tranny. Good luck.
I hope this helped you out, if so let me know by pressing the helpful button.