I played System Shock portable in last July, and this November I decided to restart it.
Replaying, I've noticed an error.

Do you know the puzzle that you must solve to block the production of robot in level 2?
Do you know the puzzle that you must solve to use the recovery bed in lever R?

Well, now the puzzle of level R is the EXACT same puzzle of level 2. I know that it is an error because it was completely different when I played in July. How can I fix it?

SSP doesn't change anything about the gameplay. Either you're misremembering or it's a feature, ie System Shock swaps/changes puzzles. But you're probably just remembering it wrong.

Edit: OR you used a different plot difficulty setting on your previous playthrough. It does mention that puzzles get harder with higher settings.