This rejection will relate to whether computations are being filed and if not the reason on page 2 of the form not being completed.

If you open the return and go to file / attachments, you need to check here whether accounts and / or computations are attached. You can remove the attachments from here if you do not want to file these with the return, for example if the company is non trading.

Once done if you then go to page 2 of the return and check questions 80, 85 and 90 to ensure that these agree to the attachments.