にもっと注意を払うべきだ

should pay more attention to

→ に
phrase Rare #44,277
should pay more attention to The に marks what someone should pay more attention to.
JA: 環境にもっと注意を払うべきだ。
EN: We should pay more attention to the environment.

君は彼の警告にもっと注意を払うべきだ。

You should pay closer attention to his warning.

君の言うことにもっと注意を払うべきだ。

I should pay more attention to what you say.

健康にもっと注意を払うべきだ。

You should pay more attention to your health.

君は彼の言う事にもっと注意を払うべきだ。

You should pay more attention to what he says.