Do I have to complete the recommended number of cervical cancer vaccinations?

A few years ago, I received two doses of the cervical cancer vaccine at intervals. The hospital originally said it was a three-dose series, but at that time I had to go abroad, so I forgot to get the remaining dose after a few months. I kept thinking I should get it but was really scared and didn't like injections, so I rationalized that two doses might be enough. Since it's a vaccination, I thought it wasn't urgent. However, people around me said it wouldn't be effective. Is it okay to get the remaining dose after several years? Has the effectiveness of the two doses worn off?