You have been doing your best and besieged thousands of castles during last week. Right? Then you recalled troops and continued besieging castles, however, you have not got any new ranking points.
Here's a thing: you receive 100 points in the weekly siege ranking each time when you besiege a castle.
The weekly ranking is updated every Monday at 7:00 AM UTC for all players around the world (even if you play from the North Pole). At that time, all Siege points earned last week are reset to 0. Hence, when you start recalling troops from the besieged castles and each time you get -100 Siege points.
How to fix this and start receiving points again?
There are 2 solutions:
1. Having recalled all your squads from the besieged castles, first, you need to besiege some new castles and earn new Siege points to reach 0 value. After that, all further Sieges will be bringing you points for the current Weekly Ranking.
2. Easier way is just to wait until the next Monday when your current negative value will be reset to 0 automatically.