Perfect foresight simulation does not change

Dear professor

I have a question.
I have a model, so I tried to make code.
But it failed. i don’t know why results do not change.
Would you help me?
dynare question.pdf (101.8 KB)
tax.mod (1.3 KB)
Thank you for reading my question.

Do not name your mod-file the same way as a variable/parameter. This prevents the correct display of error messages. The problem is that you do not correctly provide an initial condition for your model. The initval-block does not set all variables, meaning they are implicitly set to 0. But variables like k cannot be 0.