delete history problem in Maya

[Valeriya]

I don't know if somebody has already posted a question about it, but this problem is driving me up the walls!!

here is the problem:
after finishing the basic model I wanted to clean up the history on it. Went to delete history (Edit>delete by type>history) and it deleted the history but when I make any further changes to the model they never show up in the history!! For example if I smoothed the model the smooth node wouldn't show!! How to fix it? Does anybody know?

[McKronic]

make sure your construction history is turned on. When off no inputs will show up in your channel box.

[Valeriya]

thank you!

[McKronic]

your welcome!