Hi hey12,
Yes, sadly, this plugin is not meant to be set up with cracked Minecraft accounts. We may change that in a future update.
HOWEVER: Because AdPlug just launched yesterday and we want to listem to our community, I will make an exception and help you set up AdPlug with a cracked account. Please join the AdPlug discord
https://bit.ly/adplug and dm me. My username is @zushee.
Thanks for your understanding.