How to auto DM accounts on Instagram ? (bot)

Hello
My wife is singer, she subscribe to some physicals shop selling stuff for musicians, and she often receive DM from accounts which advertise some services (youtube views, ect) and I would like to know where to find these kind of services as I have a smm panel to advertise myself

I would like to find a way to target a competitor's followers list or hashtag and push them some custom DM, do you have idea to do this for cheap price? Thanks in advance

bump