how can i fix my kitchen tpa?

Check with any of the DIY outlets or local plumbers shop see if the do 'head replacements' for your mixer and replace both. Depending on the type: Remove centre cap and handle screw remove handle Udo tap head.

Capstan types have a side screw then undo chrome cover, use a cloth and wrench cloth protects the chrome. remove tap head.
Take head to any plumbing outlet in most cases better with the small shop they are more knowledgable for a replacement tap head.

BB
November 2009