diff --git a/server/api/checkin.go b/server/api/checkin.go
index 7031cec..3f45d82 100644
--- a/server/api/checkin.go
+++ b/server/api/checkin.go
@@ -28,8 +28,8 @@ type ListCheckin struct {
 }
 
 type SyncCheckin struct {
-	StartDay string `form:"start_day"`
-	EndDay   string `form:"end_day"`
+	StartDay string `json:"start_day"`
+	EndDay   string `json:"end_day"`
 }
 
 type Checkin struct {