Hi Rurangwa,
In order to achieve this try this:
1. Create a field in OHEM Table.
2. Bind this field to a Text Box on Employee Master Data Form.
3. Put some value in this Text Box on Employee Master Data Form.
4. Click on Add Button in Employee Master Data Form.
This will save your data automatically. There is no need to insert this data again using your own logic.
Hope it helps.
Thanks & Regards
Ankit Chauhan