Some problems survive because admitting the solution would require changing your behavior.

Some problems are not unsolved, they are unaccepted. You already know what would fix it, and the fix requires a change you do not want to make, so the mind keeps the problem officially mysterious. As long as the solution stays unknown, no behavior has to change and nobody, including you, can call it a choice.

Ask what you would do about a persistent problem if you already knew the answer. The response usually comes quickly. Then look at what it would cost you, and decide honestly rather than pretending the question is still open.