Is it possible to get hpv again after showing "not detected" and "clean" in my pap tests & colposcopy? have hpv16 now & cin1. and how to remove cin1??

Yes: These viruses can show up and can disappear without any obvious explanation. Your physician can advise you on whether CIN-1 even needs to be treated, or just followed closely. The key is that if you are compliant, what's happening will not be a significant danger to your life or health. In the old days, it killed millions of women. Nowadays, it's easily managed.