Contradiction between the 0 Prefaces Notebook and the Debts of the Hearts Gate of Defense

Hello Rabbi
In the debt of the hearts
It is said that one must believe with complete faith without any doubts that God is the one who causes and moves everything.
And if we want to ask Him for something, then we must believe in Him at every moment and know that He decides what will happen.

In your notebook, you wrote that belief in God is rational but uncertain, like everything else in the world.
From what you say, it appears that it is not really possible to believe with complete faith in God and there will always be a shadow of doubt.

How do you resolve or not resolve the contradiction?