Why isn't my phone fast charging?

1. Your phone has fast charging capabilities
Fast charging is supported for the following phones: Samsung Galaxy S9, S9 Plus, S8, S8 Plus, S7, S7 Edge, S6 Edge Plus, Note 5, 7, 8, 9. Please note that iPhone XS, XS Max, XR, X, 8, 8 Plus, Google Pixel 3, 3XL and all other phones that support wireless charging will charge at their normal charging rates.
2. Your phone case is not metal or thicker than 1/4 inch
3. You've placed the center of your phone on the charging pad or in the location recommended by the phone manufacturer.