diff --git a/mt76_connac_mcu.c b/mt76_connac_mcu.c
index f79e3d50..5664f119 100644
--- a/mt76_connac_mcu.c
+++ b/mt76_connac_mcu.c
@@ -310,7 +310,7 @@ mt76_connac_mcu_alloc_wtbl_req(struct mt76_dev *dev, struct mt76_wcid *wcid,
 	}
 
 	if (sta_hdr)
-		sta_hdr->len = cpu_to_le16(sizeof(hdr));
+		le16_add_cpu(&sta_hdr->len, sizeof(hdr));
 
 	return skb_put_data(nskb, &hdr, sizeof(hdr));
 }