Hi, I have a Samsung A40. After some months it wouldn’t charge via its Brick (2A Samsung Brick/transformer). It would only charge by USB on my PC. Later i found it would also charge from an Alcatel 2A Brick and an Alcatel 1A Brick. It soes not charge using my XIAOMI 3A brick. Using the AccuBattery app, it seems that the Alcatel 2A Brick produces 1.7A. I tested the 2A Samsung Brick on my XIAOMI and it produces 2.1A. It seems that the Samsung A40 will charge if i use a power source that produces less than 2A. Hope that this helps.