My L3200 doesn't have an issue with PTO disengagement. Did it a ton, but you do need to push in the clutch to make it happen. It won't do it with the clutch engaged.
Assuming you did that, yes, check the linkage. Also, keep all that linkage clean and lubricated.
I know this is going to sound odd to a lot of you, but wash your tractor regularly and lubricate everything after the wash. You will reduce wear and tear on everything, your paint will last and protect longer, and moving parts will wear less and work with greater ease.