Players are not recieving exp from monster higher level, or this monster doesnt have exp reward, please check
L2Classic official info :
Character and Classes
- The maximum character level in Lineage 2 Classic is 75.
- The level cap is planned to increase gradually in future updates.
- Penalties are imposed on the experience the character earns when it (or group) kills a monster
that is 3 or more levels below it. The penalties are greater the more levels there are between the character and the monster killed:
A character hunting monsters that are higher level than it receives no penalty and gains 100% of the experience the monster provides.