diff --git a/common/udpnat2/service.go b/common/udpnat2/service.go
index 14022118..f658fa25 100644
--- a/common/udpnat2/service.go
+++ b/common/udpnat2/service.go
@@ -27,7 +27,7 @@ func New(handler N.UDPConnectionHandlerEx, prepare PrepareFunc, timeout time.Dur
 	}
 	var cache freelru.Cache[netip.AddrPort, *natConn]
 	if !shared {
-		cache = common.Must1(freelru.New[netip.AddrPort, *natConn](1024, maphash.NewHasher[netip.AddrPort]().Hash32))
+		cache = common.Must1(freelru.NewSynced[netip.AddrPort, *natConn](1024, maphash.NewHasher[netip.AddrPort]().Hash32))
 	} else {
 		cache = common.Must1(freelru.NewSharded[netip.AddrPort, *natConn](1024, maphash.NewHasher[netip.AddrPort]().Hash32))
 	}