How long should a 22-year-old patient take medications for OCD that persists even after a year?

Hello doctor,

I am a 22-year-old male, and I am suffering from OCD (obsessive-compulsive disorder) which has affected my academic life. As a result, I often get unrealistic dreams, and I cannot concentrate on my studies. I took medicines for one year but stopped taking them in the last nine months because they were too expensive. Please suggest some medications for my problem. For how long should I take the medications? I took the following medications: First batch - Oltha 10 mg and Melzap MD 0.25 mg. Second batch - Oltha 7.5 mg, Ivacet 400 mg, and Melzap MD 0.25 mg. Third batch - Arip MT 10 mg, Zocalm 5 mg, Divaa-OD 500 mg, and Lopez 1 mg.