If you can't delete an account, a contact, opportunity or any kind of data i Cirrus, there is two reasons why.
You're not permitted to delete data.
If the "DELETE" icon does not appear this means you're not permitted to delete data in Cirrus. This can be changed by someone who has access to users in Cirrus. Change it in Settings -> Users -> Roles.
There is data connected that would be lost if you deleted it.
Cirrus prevents you from deleting data when there is active connections to the data you want to delete. For example, if you have activities and opportunities connected to an account you'll not be able to delete the account. The reason for this is that connected data would be lost and analysis would be affected.
If you still want to delete the account you need to first delete all connected information (activities, contacts, opportunities etc.)
OR
Merge the account if you have duplicates.
