Samsung M55 - Manual (Page 109)

5-9 Chapter 5. System Management
3. Align the new memory module connectors accordingly and slide it into the slot at
a 30˚ angle.
4. Push the memory module in until the module clicks into place. If the memory
module is not fixed completely, push the module while pressing the memory
module tabs outward.
5. Close and fix the memory-module compartment cover using a screwdriver.