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JobCard not showing ganttchart

hi,
I have added the sale orders and created a number of job cards for each one, but when I want to see the Gantt chart related to the job cards. Gives the following error. what is the reason?
can some one help me?

pymysql.err.InternalError: (1054, "Unknown column 'tabJob Card.from_time' in 'order clause'")