Hey Renzo !!!
My error was solved . I think the problem was when I downloaded the SimpleFTPServer library in Arduino IDE , the below section was not commented in FTPServerKey.h file , while I was using the wio terminal configuration .
// Arduino SAMD
#define DEFAULT_FTP_SERVER_NETWORK_TYPE_SAMD
NETWORK_WiFiNINA
#define DEFAULT_STORAGE_TYPE_SAMD STORAGE_SD
As and when I commented that section and compiled the code , no errors were found .
Thank you Renzo for bearing with me .