Kashering After Chag Begins

Is there any prohibition against kashering cooking utensils etc. after Pesach starts? I would like to kasher a few things I forgot the chag.


On Pesach you can only kosher using Libun. Hagalah cannot be done on Pesach

I have a pot that I am almost sure I only used once last pesach. (It’s been in my garage all year) can I use it?

You need to be sure.
Otherwise, if it’s a pot that you can kosher in the oven, its ok to kosher on Pesach. A pot or any item, that needs boiling water to kosher is out of luck