Job Position Follow-up

I applied for a job late June and had a phone interview a couple weeks later. Fortunately, I had a connection to the company through an old boss who put in a recommendation for me. The call was informal and happened mid-July and haven't heard a thing. I even sent a thank you email as well as a follow-up letting the hiring manager know I'm interested in the role. At this point, it's been over a month and uncertain about the status of the position. I don't want to seem too persistent, but also feel it's a bit unprofessional not to have said anything at this point. Do I need to wait it out, forget about it, or follow-up once more?