The rule itself is fairly clear and easy to find so unfortunately saying you didn't know isn't a very good excuse.
Some features of the badlion client aren't bad, but it has features in it like Minimap, or in your case waypoints, which can give players pretty big advantages and are not allowed because of it.
"Any form of cheating will not be tolerated
This means anything that gives you an unfair advantage over players who are playing the game the way the game was intended to be played. This includes but is not limited to: non-approved clients/software (hacked clients, clients with minimaps like badlion, external programs like autoclickers), abusing in-game glitchs (duping, 0-tick farms, x-ray, breaking bedrock) and xray texture packs."
We unfortunately don't pardon accounts that have used banned clients or mods. Appeal denied.