I bought this memory card but it looks out of the device and I think it is too bigTranscend USD300S
128 GB, microSDXC, U3, UHS-I
What am I doing wrong?
Have you plugged it in the right way round? When you insert it, it should make a noticeable "click" and then you will realise that it has clicked into place. It's best to press the card in with your fingernail :-)