Method is never called from dynamic button, does anyone know why?

Question

Hello, I create some dynamic LinkButtons in a grid that acts as a timebook, the individual "times" - the buttons can be clicked and that should call the method (editGrid).

I try to do this in the admin_pages.aspx.cs file.

Creating a similar button from code in for example in the page load works fine. But it does not work in the method "buildGui".

Can anyone see why?