diff --git a/modules/moonfantasy/api_buy.go b/modules/moonfantasy/api_buy.go
index d570051fb..a930c09d8 100644
--- a/modules/moonfantasy/api_buy.go
+++ b/modules/moonfantasy/api_buy.go
@@ -34,7 +34,7 @@ func (this *apiComp) Buy(session comm.IUserSession, req *pb.MoonfantasyBuyReq) (
 	}
 	need = make([]*cfg.Gameatn, 0)
 	for i := int32(0); i < req.BuyNum; i++ {
-		if challengeD, err = this.module.configure.GetchallengeData(umfantasy.BuyNum + i); err != nil {
+		if challengeD, err = this.module.configure.GetchallengeData(umfantasy.BuyNum + i + 1); err != nil {
 			code = pb.ErrorCode_ConfigNoFound
 			return
 		}