My router doesn’t have a notrack parameter. It does have traffic statistics, but they’re not enabled. That’s not an issue for now, as the cause of the problem became clear thanks to your answers.
The router can’t handle the increased number of connections caused by all the NTP clients in the area trying to connect to it. The issue is worse than I initially thought: not only does the score drop, but the entire internet connection for my office’s local network hangs.
Unfortunately, I won’t be keeping this NTP server active, as I can’t risk having my other servers, connected to the same network, become inaccessible. I’m very sorry for this situation.