Members are not competent to advise you.
Remember that NCLC has to be updated as per requirement in the Advertisement/notification.
You have to inform facts both in your application for employment and to Tehasildar for updating the income certificate.
If you state as married your spouse income has to be clubbed as per norms.
You can not state that you are unmarried as it amounts to suppression of facts to derive a benefit.
If you can convince the Tehasildar and if the Tehasildar can issue such certificate after marriage based on the income of your parents, the certificate is valid.
It is the decision of Tehasildar finally either to issue such latest certificate or cancel the certificate after receiving your latest renewal application.