Question regarding sequencefile


hi when i am saving data in sequence file format with single key and value pair, its getting saved and i am able to read the data by using "sc.sequenceFile(‘file path’) " whereas when i am saving data in single key with multi value pairs format i.e (K,(v1,v2)) form, file is getting saved in sequence format but when trying to read using “sc.sequenceFile (‘file path’)” its throwing error. can you please explain why its happening