Sorry to hear about the trouble. Please try the suggestion shared in this similar discussion: https://community.adobe.com/t5/adobe-xd/adobe-xd-cc-there-was-a-problem-creating-a-new-cloud-documen...
Let us know if this helps or if you need any further assistance.
I followed the same steps . but now i am getting error code 3636 while creating new document.
Thank you for trying the steps that Rishabh provided. As you have encountered a new error here. Please try the steps mentioned here (https://helpx.adobe.com/xd/user-guide.html/xd/kb/fix-issues-with-xd-cloud-documents.ug.html)
Let us know if that helps.