diff --git a/plugins/weixin_cpn/internal/util.go b/plugins/weixin_cpn/internal/util.go
index a5b5a5e..3e41d8d 100644
--- a/plugins/weixin_cpn/internal/util.go
+++ b/plugins/weixin_cpn/internal/util.go
@@ -10,25 +10,23 @@ import (
 	"sync"
 )
 
-var instance *cashcoupons.CouponApiService
 var once sync.Once
-var onceError error
-var onceErrorMutex sync.Mutex
+var errorMutex sync.RWMutex
 
-func getSrv(ctx context.Context, config *Config) (*cashcoupons.CouponApiService, error) {
-	onceErrorMutex.Lock()
-	defer onceErrorMutex.Unlock()
+var instanceMap = make(map[string]*cashcoupons.CouponApiService)
+var errorMap = make(map[string]error)
 
-	if onceError != nil {
-		instance = nil
-		onceError = nil
+func getSrv(ctx context.Context, c *Config) (*cashcoupons.CouponApiService, error) {
+	errorMutex.Lock()
+	defer errorMutex.Unlock()
+	if errorMap[c.MchID] != nil {
+		instanceMap[c.MchID] = nil
+		errorMap[c.MchID] = nil
 	}
-
 	once.Do(func() {
-		instance, onceError = newInstance(ctx, config)
+		instanceMap[c.MchID], errorMap[c.MchID] = newInstance(ctx, c)
 	})
-
-	return instance, onceError
+	return instanceMap[c.MchID], errorMap[c.MchID]
 }
 
 func newInstance(ctx context.Context, config *Config) (*cashcoupons.CouponApiService, error) {