Keep not being able to close the deal on 2nd rounds - interview advice?

I've been running into a number of situations where my resume/network has gotten me in the door, I do well on the first round, but I've been getting to the finish line a lot and not being able to close the deal. Most recently was for an ER position that I wanted in Houston. Some if it may just be bad luck, but I want to make sure that my interview game is tightened up as well. I've read the WSO interview guides, and they were very helpful and I think the reason why I've been doing well in first rounds and getting to the second stange. However, I just haven't seen the results in terms of closes.

Have any of you been through something like this, and what did you do to overcome it?

Background on myself: worked in PWM for just under 4 years, CFA Level III Candidate, undergrad degree in economics from a target. My aspirational goals are HF/PE, but I realize I don't have the traditional ER/IB background for that, which is why I have been seeking ER positions (was my main goal out of college) as well as corporate finance positions. Wealth management was really more of a way to pay the bills for me than anything.