A job can be deleted in the Web Portal and in the App.
To delete the job, Web Portal > Jobs > View Jobs > select the checkbox for the job/s that you wish to delete > select Delete at the bottom of the screen.
Delete jobs can be viewed in the Web Portal > Jobs > Deleted Jobs. From here jobs can be restored by selecting the checkbox(es) for the job(s) that you would like to restore > Restore.
To search for jobs that you have rejected in the app among your Jobs, you can apply the status filter of 'Status is Rejected' in the Web Portal (see image below), from here you can select the checkbox(es) for the job/s to then delete them; select Delete action at the bottom of the screen.
In the App Diary, hold down on the job, pop up will appear > Archive.
In the Job list you can swipe to the left to archive a job.