Practice versus teaching. Indulgences are still given, though the practice (not teaching) of indulgence granted for monetary contributions to the Church are explicitly forbidden by the Council of Trent. The practice was an abuse.
Was the practice taught? Was it encouraged? Did one person go away thinking he had done that which is right by the Lord because the Pope said it was right? Remember what Paul taught. That which I do, put into practice. If the Pope encouraged it, it was practiced, desired, and in ERROR.
What is the reason for indulgences? Forgiving of sins? Only Jesus can forgive a sin, not a Pope, not Mary, not a Saint, nobody but Jesus, and he don't need your money to do it.