diff --git a/es/checkers/order.js b/es/checkers/order.js
index 5b0b412a..ca70b4fe 100644
--- a/es/checkers/order.js
+++ b/es/checkers/order.js
@@ -44,8 +44,7 @@ const checkers = [
                 const { price, paid, iState, allowPartialPay } = order;
                 assert(['unpaid', 'partiallyRefunded'].includes(iState) && paid === 0);
                 const { pay$order: pays } = data;
-                assert(pays instanceof Array);
-                if (!pays.length) {
+                if (!(pays instanceof Array) || !pays.length) {
                     throw new OakInputIllegalException('order', ['pay$order'], 'error::order.nonePay');
                 }
                 let amount = 0;
diff --git a/lib/checkers/order.js b/lib/checkers/order.js
index b438bea9..6eb640b0 100644
--- a/lib/checkers/order.js
+++ b/lib/checkers/order.js
@@ -47,8 +47,7 @@ const checkers = [
                 const { price, paid, iState, allowPartialPay } = order;
                 (0, assert_1.default)(['unpaid', 'partiallyRefunded'].includes(iState) && paid === 0);
                 const { pay$order: pays } = data;
-                (0, assert_1.default)(pays instanceof Array);
-                if (!pays.length) {
+                if (!(pays instanceof Array) || !pays.length) {
                     throw new types_1.OakInputIllegalException('order', ['pay$order'], 'error::order.nonePay');
                 }
                 let amount = 0;
diff --git a/src/checkers/order.ts b/src/checkers/order.ts
index f386f53c..c2d16379 100644
--- a/src/checkers/order.ts
+++ b/src/checkers/order.ts
@@ -53,12 +53,11 @@ const checkers: Checker<EntityDict, 'order', RuntimeCxt>[] = [
                     assert(['unpaid', 'partiallyRefunded'].includes(iState!) && paid === 0);
 
                     const { pay$order: pays } = data;
-                    assert(pays instanceof Array);
-                    if (!pays.length) {
+                    if (!(pays instanceof Array) || !pays.length) {
                         throw new OakInputIllegalException('order', ['pay$order'], 'error::order.nonePay');
                     }
                     let amount = 0;
-                    pays.forEach(
+                    pays!.forEach(
                         ({ action, data }) => {
                             assert(action === 'create');
                             const { price } = data as EntityDict['pay']['CreateSingle']['data'];