It can take up to a year of regular intercourse for you to get pregnant, that's not unusual or necessarily a concern. But, as you know, untreated chlamydia can cause scarring and cause fertility problems. Whether or not that is the case we can't know. You'd have to see your ob/gyn and have them check your fallopian tubes for scarring.
Get the chlamydia treated first, BOTH of you need to go. Then, no sex until cleared. That means you BOTH go back for a followup test. As you found, sometimes the medication does NOT work.
How long have you been trying regularly to have sex? If more than a year both of you should see a fertility specialist to find out what is going on. You can expect a full internal exam with blood work. Your partner can expect a semen analysis. It might be him.
Hope it helps.