Is the surf map you are playing course or deathmatch map?
If the map is designed to be course, it will automatically just teleport you to the previous checkpoint.
https://gamebanana.com/maps/cats/7237
Look at right corner. There is Combat Surf and Skill Surf. You are looking for skill.
If its just specific map that is broken then just delete it.
Unless you want to create dev zones that teleport them.
Also you can just use
https://forums.alliedmods.net/showthread.php?t=265456
This is not outdated like ckSurf and will count time that it took player to pass from point A to point B.