Why do I feel like this?

Hi all. Looking for some honest advise or not sure what I'm looking for. Recently I've just been unhappy at work, I quit my last job thinking another job/another role would make me happy so I accepted it. It was more money (about 50k more). My previous employer really wanted me to stay, saying they would promote me etc ( story for another day) - when leaving they said every company has its own problems. And currently I find myself unhappy in my new job. I wonder if it's karma as their words keep haunting me. Basically the work I'm doing now is not impactful at all, 70% is like approving invoices or troubleshooting the invoicing system lol- I have a strong technical background in data & Analytics and project/program management and I strive on the fast pace life of projects which I'm not getting out of this role. Recently I got rejected from apple (twice at the final on site) and I've just been feeling really unworthy because of those experiences as well. I've already spoken to my current mgr about the lack of meaningful work I'm doing.I could continue passing day by day but I feel it's a waste of my skills that I've worked so hard to achieve. What should I do? Am I being ungrateful? I'm so worried about my career that it's all I think and worry about...I'm also constantly networking and applying for various jobs...what else can I do to keep my morale high/deal with job rejections/keep myself motivated etc? Tc 165