diff --git a/dns/doh.go b/dns/doh.go
index 08d0d172..81af438c 100644
--- a/dns/doh.go
+++ b/dns/doh.go
@@ -81,7 +81,7 @@ func (dc *dohClient) doRequest(req *http.Request) (msg *D.Msg, err error) {
 		} else {
 			if dc.firstTest.CAS(true, false) {
 				dc.supportH3.Store(true)
-				_ = dc.transport.CloseIdleConnections
+				dc.transport.CloseIdleConnections()
 				dc.transport = nil
 			}
 		}