ffmpeg how to remove black background overlay image on video

'ffmpeg -y -i video.mp4 -i bells_sticker.png -filter_complex "[1:v]rotate='90*PI/180:c=black@0'[rotate];[rotate]scale=238:238[b];[0][b] overlay=100:50:enable='between(t,0,20)'" -codec:a copy StickerWithVideo.mp4'

I get black background behind the input image

try also this for remove background

c=0x00000000 c=none

Outout

Original Sticker Image

i'm say thanks in advance