I'm adding a custom field to time and costs. but I can't add these custom fields to columns. and when I export to excel file, custom fields do not appear, defaults appear. Can I see the custom fields I added in the time and costs section to the field I marked in blue? And I want to see the custom fields when I export them to excel.

Hi Mertcan, 

We have feature request OP-8078 regarding including custom fields in the cost report export (XLS). 
I have added a vote for you. 

Best regards
Samantha

Thank you Samantha,

Hi Mertcan,

We have feature request <mention class="mention" data-id="35760" data-type="work_package" data-text="#35760">#35760 regarding including custom fields in the cost report export (XLS). 
I have added a vote for you.

Best regards
Samantha