On the 11th of December 2023 during a call with one of the customer service agent, I requested my debit order to be amended to the 25th of each month

On the 11th of December 2023 during a call with one of the customer service agent, I requested my debit order to be amended to the 25th of each month. I was told it will be effective from January, but this morning the debit order went trough. Although the agent confirmed it was changed