diff --git a/apps/auctions/volume_matching.py b/apps/auctions/volume_matching.py
index 5a3c0db78..f46066d2d 100644
--- a/apps/auctions/volume_matching.py
+++ b/apps/auctions/volume_matching.py
@@ -43,7 +43,8 @@ async def compute_bids(ctx, balances, bids, price):
                   In volume matching, price is determined by reference to some external lit market. Price is how much
                   units of ETH have the same value as one unit of token.
     :return: buys, sells
-             This function returns two lists of bids for buy and sell respectively.
+             This function returns two lists of bids for buy and sell respectively. Since we have separated buy and
+             sell bids, now every bid has volume larger than zero.
     """
 
     one = ctx.Share(1)
diff --git a/tests/test_volume_matching.py b/tests/test_volume_matching.py
index 6b67f9d73..d404e389f 100644
--- a/tests/test_volume_matching.py
+++ b/tests/test_volume_matching.py
@@ -57,7 +57,7 @@ async def _prog(ctx):
             assert _sells[i] == s[i]
 
         matched_buys, matched_sells, res_buys, res_sells = await volume_matching(
-            ctx, (buys, sells)
+            ctx, buys, sells
         )
 
         _matched_buys = [await x[1].open() for x in matched_buys]