Your phone supports an optional microSD card up to 512 GB.
The type to buy depends on how you'll format the card:
Portable storage (can use card in different devices): A Class 2, 4, or 6 card is sufficient.
Internal storage (card used only by phone): Use a high speed card such as UHS-1 type for best performance. Class 2, 4, or 6 cards are slower than your phone’s internal storage, so using them for internal storage would slow your phone's performance.
Learn more about the differences between portable storage and internal storage.
Insert the SIM tool into the tray hole and gently push to pop it out.

Insert or remove the cards as needed.

Push the tray back into the phone.

What type of issue do you have?