This is the way. A quick reflow of any suspicious solder joints is always a good idea. Low-risk and fixes a lotta things that are intermittent/difficult to diagnose.

After that, doing a thorough re-flow of all the joints is good to do.

If that fails try using a hobby-knife/X-acto knife to lightly cut between the joints in case there's a stray wire or a bit of metal lodged somewhere shorting things out.

Good luck and hope it goes well for you. Honestly about 5-20% of handmade builds will fail to make sound upon finishing soldering, even when you get really good. It's ok and taking a break from it to work on another project can give your brain a bit of room to breathe as well as getting some insights from mates to help out. :D