diff --git a/src/csharp/ext/grpc_csharp_ext.c b/src/csharp/ext/grpc_csharp_ext.c
index 8e2a5f0269a9b92cbe932e59128041b21b4499a7..28c2791cac000763f30c57a3b78dfba15db81f6e 100644
--- a/src/csharp/ext/grpc_csharp_ext.c
+++ b/src/csharp/ext/grpc_csharp_ext.c
@@ -390,7 +390,7 @@ grpcsharp_channel_check_connectivity_state(grpc_channel *channel, gpr_int32 try_
 GPR_EXPORT void GPR_CALLTYPE grpcsharp_channel_watch_connectivity_state(
     grpc_channel *channel, grpc_connectivity_state last_observed_state,
     gpr_timespec deadline, grpc_completion_queue *cq, grpcsharp_batch_context *ctx) {
-  grpc_channel_watch_connectivity_state(channel, last_observed_state, NULL,
+  grpc_channel_watch_connectivity_state(channel, last_observed_state,
                                         deadline, cq, ctx);
 }