You must have the according fsc script to flash this device. xperia e3 d2203

i wanted to flash new firmware 18.5.C.0.25 on xperia E3 D2203 using flashtool 0.9.19.5.
it's giving error message "You must have the according fsc script to flash this device"
i'm new to flashtool and appreciate if someone help me on this
thanks in advance