Activate SharePoint design

[ManarYazji]

Hi there,

I have a SharePoint site and I want to access it throw Sharepoint design but I can't!:persevering_face:

This message appears when I connect to the SharePoint site. 

I really need help with this issue.

Thanks

[#2]

The screenshot clearly shows that's because of the permission. Which version of SharePoint and if it is On-Prem, can you please check the Sharepoint designer settings in the Central Admin.