correct data type.

Author: RustNinja

vesting-backend/src/main.rs

@@ -206,7 +206,7 @@ pub async fn submit_signature(
 
             if !exists_data_in_file(path_to_drop_file, droped_item.address.clone()){
                 dropped_data.push(droped_item.clone());
-                let json_data = serde_json::to_string(&droped_item).expect("Unable to serialize");
+                let json_data = serde_json::to_string(&dropped_data).expect("Unable to serialize");
                 std::fs::write(path_to_drop_file, json_data).expect("Unable to write file");
             }