According to the operating instructions, this should work with the star button (bottom left on FB):
Press and hold to open the preset memory menu;
Press briefly to open the preset menu.

Alternatively, perform a reset as described on page 26:

"Delete all settings (reset)
This function allows you to reset all customised
all customised settings to the factory settings. In this case, all settings will be lost.
1 Open the menu by pressing and holding the
pressing and holding the
"MENU/INFO" BUTTON.
2 Select the "System settings" option with "r
e" and confirm by pressing "OK".
3 Select the "Factory reset" option with "r e"
and confirm by pressing "OK".
- A security confirmation is displayed
4 Press "r" to select the "Yes" option.
Note:
7 To cancel the function, select the "No" option by pressing "e".
5 To confirm the setting, press
"OK".
- Display: "Restarting".