Morris, 23, was last seen Aug. 30, 2014. Her car was found locked in a parking garage the next day at the Shops of Legacy in Plano, and no one has been able to contact her since then.
Morris' friend, Enrique Arochi, was arrested in December in connection to her disappearance. Police said DNA samples collected earlier in the investigation from Arochi's car were a match to Morris' DNA.
The last time Morris was seen, Arochi was seen on surveillance video walking with her into the Shops of Legacy parking garage.
Fundraisers for the investigation led to the reward increase.
Tips can be submitted through the North Texas Crime Stoppers hotline at 1-877-373-TIPS or via http://www.ntcc.crimestoppersweb.com/.
Plano police can be contacted at 972-424-5678.