diff --git a/src/tbf_ul.cpp b/src/tbf_ul.cpp
index e1a0fbd..55c83e7 100644
--- a/src/tbf_ul.cpp
+++ b/src/tbf_ul.cpp
@@ -153,7 +153,7 @@
 		return NULL;
 	}
 	bitvec_unhex(ack_vec, DUMMY_VEC);
-	Encoding::write_packet_uplink_ack(bts_data(), ack_vec, this, final, rrbp);
+	Encoding::write_packet_uplink_ack(ack_vec, this, final, rrbp);
 	bitvec_pack(ack_vec, msgb_put(msg, 23));
 	bitvec_free(ack_vec);