Who I have the same questioned this solution

Remove the smaller card from the phone. Install the new larger card and format it as internal memory. Remove larger card from phone. With a computer copy the entire contents of the smaller card to the new card by copying the contents temporarily to a folder on the computer. If you have a means to read both cards at the same time, you can copy the contents directly from one to the other. When the contents are copied, insert the new card back in the phone.