You gotta be more careful, Usually servers do have a plugin called "Anti-Cheat" that helps bank whoever's cheating, sometimes they are light and slight cheats wont be detected (example using airjump instead of flight), and other servers uses heavy anti cheats, these often check for anything remotely suspicious, like breaking a block slightly furthen than you're supposed to do so (Reach hack)
so probably the server has anti cheats and you cant do anything but play other servers, and use the Support tag. not the Development Tag
