[Script] hidesprite reappears after moving

Hi, i'm trying to make a sprite disappear after a battle. It does, but after I take a step it reappears. Here is my script, please let me know if I did something wrong, i'm new to this.

#org @after
msgbox @defeat 0x2
fadescreen 0x1
setflag 0xFD
hidesprite 0xB
fadescreen 0x0
release
end

Also, the Person ID I have as FD, do I need to have it as 0253 instead?

I also just started learning scripts and I don't understand anything about your part
this script(may be full script ,i know). I used the Diego tutorial and it seemed to work.//we check the flag. if it is zero, it means it has never been used. and after activation we put one.human id must match the flag and no transfers to other systems are needed

#dynamic 0x800000

#org @start
checkflag 0xfd
if 0x0 call @1
lock
faceplayer
msgbox @1 0x6

cry 0x6 0x0
wildbattle 0x6 0x1E 0x8B
fadescreen 0x1
fadescreen 0x0
hidesprite 0x800F
setflag 0xfd
release
end

#org @1
= CHARIZARD: Raaarrgghh!

You should use 'safe' flags, check this thread to check which are safe to use: https://www.pokecommunity.com/showthread.php?t=302347