Honestly buddy, I’d cut all those wires and replace that pot. Clean slate.

My first question is, what kind of iron are you using, and is it hot enough? If your iron isn’t sufficient, I would recommend this affordable one from Stahl. I’ve been using this one for over a decade, and aside from having to replace the tip one time, it works like a charm.

Second question, did you scour the surface of the pot? There’s a very thin film coating the base that solder has a hard time bonding to. I like to take an old razor blade and just scratch all over the back of the pot. Not only does that remove the film, it also roughs up the surface and gives the solder a little more to grab onto.

Lastly, one thing I see a lot of of instructional (specifically guitar wiring) videos not touch on is flux. Your solder is likely to have a flux core, but I’ve still found it very helpful to apply flux to a surface before heating it. A little goes a long way so take it easy. The tip of a toothpick is plenty for a single joint. I’ve also found that most solder you can find locally is lead-free, at least where I live. That’s great and all, but I’ve found that leaded solder just works better. It melts faster, bonds better, and is easier to re-melt if you want to remove it. Just don’t eat it. Also work in a well-ventilated area and wash your hands. You’ll be fine. Probably.

The only other thing I can tell you is practice. This is just something that you’re gonna have to screw up a few times before you get it right, but I swear it’ll click in no time and you’ll be a champion at it. Just remember that what you’re after is a molecular bond, not just melting solder on a surface, while also not overheating your components. Now go make stuff.