Roof Leak

[moorem]

Hi guys. I installed a new bathroom fan a while ago and it vents to an angled, shingled roof. After a couple months it started leaking when it rains really hard. I climbed on the roof and couldn't find anywhere that I thought rain could get in, and also looked in the attic around the hole I cut while it was raining. it was dripping in through the hole sure enough.I bought some henrys wet patch cement and applied it EVERYWHERE I could imagine it could possibly be coming from. It didn't work, Rain came in the next time it rained. My question is, is there a clear sealant I can "paint on" the whole 2 x 2 area of the roof to help seal it? Or should I call a pro in? Its not a flood but it is about a drop a second coming in through the hole. Any help would be greatly appreciated. Thank you. [V]