StatsD repeater backends cause data lose

We have a statsd run on UDP and InfluxDB backend worked fine, until the day before yesterday when we add a repeater backend to the statsd instance. Repeater send data to another statsd and there is a backend write by ourselves, for some extra analysis. At first the two statsd worked fine, but at 20:00 yesterday, the problem came. We use grafana with InfluxDB backend, and the counter shows only 50/s which should be aoubt 100/s (tps of an api). And same at tonight 20:00. (traffic going heavy at the time.) I remove the repeater backend and restart the statsd, all things going to be ok. How should I resolve this?