This may be true or false depending on the situation.
Step-by-step explanation:
If countering in the inflation, banks were giving negative values all the time to their consumers they would not survive in the game.
But this is not to say this is not a practice that has been done to the unsuspecting people who have wanted to invest money.
They are being given policies and rates that after countering inflation are actually in loss for them as they do not grow as much as the money would have devalued by then.
This is however quite rare and is a malpractice.