Question about Samsung Galaxy A25

The phone effectively has 2 SIM slots and 1 SD card slot, with the second SIM slot being hybrid. This means you can either use two SIM cards at the same time or one SIM card and one SD card for memory expansion, but not all three at the same time. So there is no separate third slot just for the SD card.

Then it is not true that the device can hold 3 cards at the same time.