There is a great chance you are reinfected due to not using condoms.
When there is a chance that you have been reinfected or you are continuing to have the same symptoms although you have finished the therapy, you should go to the clinic to be retested.
Any and all sexual partners, should be treated or tested so the infection is not passed back and forth.
What kind of antibiotic you have received?
Was this infection found accidentally or you had certain symptoms?