Import undo processes stuck for weeks

Import undo processes stuck for weeks

We use the .xls leads import option on ZohoCRM and sometimes we do need to use the undo option on import history. Our issue is that sometimes undo processes doesn't get completed and we have undo processes more than month old stuck in the queue. 

What could be the issue ? Tried contacting ZohoCRM support team before posting the question here  https://support.zoho.com/portal/zohocorp/home and waited few days for a reply. Now I couldn't even log in to that because it says Invalid Email Address or Password

-Ruchira