2003 Dodge Neon oil light

Computer problem
2003 Dodge Neon 4 cyl Two Wheel Drive Automatic

While traveling, I exited the freeway and got to the light. My oil light came on. I went and had my oil changed. The light kept coming on. I had the oil pressure sending unit changed and had another oil change done about 4 days later. The light kept coming on. I traveled to TX from TN. The light came on once we got to TX and it still just keeps coming on. What is causing this and what can I do. Could it just be a glitch or is it something major. Plz help.