Hi Maria,
Based on your description, after you insert a chart, the Chart Design tab doesn't appear. We'd like to confirm some information to clarify your situation.
- If you click the data in the table then select the chart again, will the tab appear? If possible, please share the screenshot of the symptom after you select the chart.
- Does this problem happen to all the workbooks you have? You can try creating a new workbook with the same chart then check whether the problem still persists.
Regards,
Tisky