Running

Knee pain could be ligament, muscle, meniscus, or other, or all.

My frame of reference is knee pain brought about by a combination of weight gain, muscle loss (particularly around the vastus medialis), exacerbating poor control, leading to inflammation around the medial collateral ligament, and general scrawnchiness of the meniscus.

Treatment was initially neuromuscular exercises to bring wayward motions back into check, then transitioning to strength work, from general (squats), to specific (single leg stiff deadlift, or split squat with banded extensions), to extremely specific (seated banded oblique leg extension to target the vastus & nothing else).

You experience may be any combo, or none, of the above, and even if the same, an effective treatment may be any combo from all to none of the above.

Seeing two physio has fixed it (fingers crossed) for me - you may be luckier!