diff --git a/relay/adaptor/gemini/adaptor.go b/relay/adaptor/gemini/adaptor.go
index edae1791..e6e4d051 100644
--- a/relay/adaptor/gemini/adaptor.go
+++ b/relay/adaptor/gemini/adaptor.go
@@ -7,6 +7,7 @@ import (
 	"net/http"
 
 	"github.com/gin-gonic/gin"
+
 	"github.com/songquanpeng/one-api/common/helper"
 	channelhelper "github.com/songquanpeng/one-api/relay/adaptor"
 	"github.com/songquanpeng/one-api/relay/adaptor/openai"
@@ -29,6 +30,8 @@ func (a *Adaptor) GetRequestURL(meta *meta.Meta) (string, error) {
 		"gemini-2.0-flash-thinking-exp",
 		"gemini-2.0-flash-thinking-exp-01-21":
 		defaultVersion = "v1beta"
+	default:
+		defaultVersion = "v1beta"
 	}
 
 	version := helper.AssignOrDefault(meta.Config.APIVersion, defaultVersion)