No Return Offer - Advice Moving Forward?

Devastated. I’m pretty shocked that I didn’t receive a return offer from my top MM. Throughout the summer, I received great feedback from the analysts and associates I worked with, felt like I got along well with everyone, and was never given any indication that I wasn’t in good standing for an offer.

The feedback they gave me at the end was very limited and focused on a minor "mistake" from when I first hit the desk—something I corrected and never thought twice about afterward. This was also completely different from my mid-summer feedback, which was very positive, so the decision still doesn’t make much sense to me. Group did have a 50% cut. 

I didn’t love the group I was placed in and was already re-recruiting for other opportunities. However, since telling those firms that I didn’t receive a return offer, it seems like most of those opportunities are not in play. 

Regardless, I know 100% that I want a career in IB, so I’m trying to put this behind me and figure out the best way forward. If anyone has been in a similar situation and successfully re-recruited, I’d really appreciate hearing about your experience and any advice.